Absorption Coefficient  (SABIN)

The % of incoming energy that is absorbed. In measuring radiant energy (light or heat) it’s a unitless ration that may vary depending on wavelength.  In acoustics, it’s called a SABIN and may vary depending on frequency.

Absorption Refrigeration

A cooling process resulting from the absorption of vapor by a brine solution that is then heated up to remove the moisture.  The heat may be supplied by solar or other heating properties.

Absorptivity (a)

Measure of reflectivity/absorptivity – measured in SABINS

T=. 05V/A

T= reverberation time, A=area of space (cubic feet), V=absorptivity factor

Absorptivity affects reverberation time, and the # of all dB resulting from all sound sources in the space, and makes a space LIVE or DEAD,.

Abney’s Law

Light arriving at a surface is the sum of all the light arriving from all the sources and can be expressed by repeating the Point Grid Formula for each source:  E=I1cos1/d12+I2cos2/d22 + Incosn/dn2      REFLECTED LIGHT NOT CONSIDERED

Acidic

Lower # on the pH scale…0-6.9 are acids….sulfuric and nitric acids cause corrosion in metal pipes, pollute water and air.

Acid Rain

Nox – nitric oxide – kills fish in water

AC

Abbrev. For air conditioning – or – alternating current

Acoustics

Attenuation and distance – see NRC vs. STC definitions
Absorption
Diffusion
Transmission
Methods of Noise Reduction
Openings in Sound Barriers
Sound reduction over distance

Acoustic Tile

Reduces airborne sound in a space, does not stop transmission between spaces.

Acoustic Power Level

Logarithmic expression for the acoustical power at the source of a sound.  Also known as the Power Level (PL).

Active Systems

Solar Design Systems where the collector device and storage device are separate.

ADA fixture requirements

36” wide entries
60” turning clearances for 10” above floor
Rim of urinals 17” above floor
Controls 44” above floor
Lever-type handles
Clear space of 30”x48” in front of fixtures

AHU

Air Handling Unit.  Heart of HVAC system.  Comprised of blowers, fans, filters, heating and cooling coils, and a drain pan.  Heats, cools, humidifies, dehumidifies, filters and supplies and returns air.  Three types:

• Central…require large mechanical space(s), complex controls, and distribution trees

• Unitary…single package, can be separately metered

• Furnace…heat exchanger, with ducted distribution

Air

Warm air expands, reduces density, becomes lighter, and rises.
Cold air is denser, heavier and falls.  Moisture condenses in colder air.

Air Change Method

Used to determine air infiltration. 

Qcfh=NxV

Quantity of infiltration per hour=Number of required air changes x Volume of space

Air Conditioning

Cooling of air, treatment for temp., humidity, air quality and circulation.

Air Gap

Unobstructed vertical path, open to the atmosphere, that separates the faucet’s outlet from the overflow rim of the fixture it serves.  Prevents momentary vacuum in a supply pipe from siphoning water from the fixture back into the supply.

Alkaline (basic)

Higher #s on the pH scale (7.1-14) – means material is BASIC

Altitude  (ALT)

Height of sun in the sky, affected by time of day.  Use with AZIMUTH to determine sun’s position relative to the site at any given time of day.

Alternating Current

Electric current which reverses its electron direction at regular intervals, generally 60 x per second. 
A plot of the voltage over time is a sine wave.  Voltage is always changing causing flow direction changes. 
Utility companies generally provide power at AC operating at 60 hertz.

Aluminum

Bauxite

Aluminum Wiring

Discontinued for small gages (#4 or less) – it oxidizes, causing metal fatigue, and connections deteriorate.  Copper wiring is preferred.

Ambient

A general or all-surrounding condition. 

• Acoustics = background noise level

• Lighting = background light level (no shadows, diffuse light)

• Thermal Processes = air temp (not temp of surfaces or objects)

Amperage/Amps  (FLOW)

I (amperage)=Voltage/Resistance

Unit for measuring the amount of electrical current flowing in a circuit.  
1 Volt applied across a resistance of 1 ohm will cause 1 ampere to flow. 
A=W/V

American Wiring Gage (AWG)

Wire sizes are standardized using AWG.  No sizes smaller than 14 gage used for building wiring.

Amorphous Silicon Cell

Cheapest, most common photovoltaic cell  – used in handheld calculators.

Amplitude

Magnitude or INTENSITY of sound.  Loud sounds have great amplitude, with more energy stored in the sound wave.

Angle Valve

A/k/a SCREW & SEAT valve, or WAHSER & SEAT valve.
Flow restrictor or metering valve, similar to a globe valve.

Anode

A piece of metal inserted in a water tank to collect hard water deposits to keep them from forming on the heat exchanger.

ANSI A117.1

National Standard for electrical codes.  States also have codes.

ASHRAE

Abbrev. For American Society of Heating, Refrigerating and Air Conditioning Engineers (1975 manual)

Aspect Ratio

Ratio of the longer to shorter dimensions of an air duct, which affects duct friction.
Ratio of the longer to shorter dimensions of a room, which relates to light reflection.

Artificial Light Levels

Calculate by:
ZONAL CAVITY METHOD A/K/A Room Cavity Method – or – Lumen Method  
Used for uniform distribution of a large # of fixtures. 
Considers direct lighting, ceiling reflectivity, wall mid level, zone between work surface and floor, and maintenance and dirt.
Based on CU (0-1 range, most fall between .5 and .8)
- or -

POINT GRID METHOD

E = cos 0/d squared

• E=illumination at receiving surface

• 0 = intensity at the source when viewed from direction of receiving source

• d= distance from source to surface

Automatic Fire Recall System

Code requirement – system immediately returns all elevators to a set floor where they park with open doors.

Azimuth  (AZ)

Sun’s relationship to north and south (compass orientation of the sun) – affected by time of day.

Backflow Preventer

A/k/a CHECK valve.  Prevents water from moving back into the system (prevents contamination of the supply)

Background Noise

A/k/a MASKING or WHITE noise…. allows for speech privacy

Ball Drip Valve

The automatic drain valve at the base of a dry standpipe.

Ballast

Component of florescent and high intensity discharge lamps that controls voltage and current in order to provide circuit conditions that are needed to start and operate a lamp.  Ballasts produce noise and heat.

Basic (alkaline)

On a pH scale of 14, any solution having a pH above 7.

Batch System

Active solar system – (nearly passive) – storage tank is exposed to the sun. Nicknamed “breadbox”.

Bioterrorism attack

Where would radioactive material collect? (trick – BIO MTL!)
Best location in wall for an air vent (trick! Radioactive means nuclear attack)

Blow Down

The drain that removes dirt that builds up in the floor pool of an evaporative cooling tower.

Boiler

Tank or heat exchanger tube used for heating water

Boiler Parts

Fuel, heat source, a pump or fan, a heat exchanger or terminal, and a control system.

Breadbox

Nickname for Batch System – active solar system – (nearly passive) – storage tank is exposed to the sun.

BTU

British Thermal Unit
Unit of heat energy – defined as the amount of heat required raising the temperature of one pound of water by one degree Fahrenheit.

To calc BTU to heat water = weight of water (lbs) x temp needed to rise

BTUH

BTUs per Hour – an energy flow rate

Building Automation

Control of automatic multi-functional equipment in a large building – usually includes the HVAC system, the fire detection and alarm system, lighting controls and building security.

Building Energy Perf.  Standards

BEPS  - Federal performance code that specifies energy budget per square foot for different buildings.

BX Cable

Factory assembled – cannot add wires in the field.  Similar to FLEX, cannot go underground or be embedded in concrete.

Busbars

Rectangular copper bars used to conduct high currents of electricity. Power is transmitted thru multiple bars, insulated from one another, arranged in a metal housing called a busway.

Calcium

Mineral component of hard water.  Limestone is Calcium chloride (CaCO3)

Candela

Candlepower

Candle Power (cp)

Measure of the luminous intensity of a light source.  The amount of light emanating from one candle or one candela.

Candlepower Distribution Curves

Polar plots of fixture intensity.  Shows how much light is given off @ any angle from a vertical reference line.

• Direct

• Semi direct

• General Diffused (Diffused Enclosed, Direct & Indirect)

• Indirect

• Semi Indirect

Capacitators

2 plates separated by a small insulating layer. Current is stored on one of the plates, then all energy is discharged.  Used to improve power factor in a circuit, improves efficiency and performance.

Catch Basin

Collects water run-off in storm system. Similar to a manhole, top has a n open grate.  Laced at lowest part of a swale or depression.

Centrifugal Fan

A/k/a a “squirrel cage blower”, moves huge amounts of air.

Central Heating Classifications

Classified by heat carrying medium (steam/air/water) or by energy source (electricity, liquid/solid fuels or solar)

Cesspool

Underground chamber w/porous bottom – allows seepage of waste to adjacent ground. Outlawed by most codes.

CFM

Abbrev. For “cubic feet per minute”, the flow rate of air in a mechanical system or duct.

Circuit Breaker

Devices that automatically disconnect a circuit when current is excessive.

Circuit Vent

In sanitary drainage, any vent that serves two or more traps.

Characteristics of Smoke Detectors

Fire alarm systems that contain a photoelectric detector that responds to smoke before the fire breaks out.  They may be activated under false conditions, such as kitchen smoke or dust.  Used in offices and apartments buildings.

Check Valve

Prevents water from moving backwards in a system (backflow preventer)

Chiller

Equipment that cools water for use in an air conditioner system.  Uses refrigerator cycle.

• Heat added to refrigerant in evaporator and compressor

• Heat removed from refrigerant in condenser.

Chill Factor

Fictitious temperature assigned to a combination of actual temperature and wind velocity that has the same physiological effect as still air at the chill factor temperature.

Chlorination

Addition of small amounts of chlorine to a water source to kill bacteria.

Chlorofluorocarbons (CFC)

i.e., FREON – special fluid circulated in a refrigeration loop to cause temperature changes (evaporation and condension)

Cleanout

Y shaped pipe fitting with screw on caps – allows one to snake blockages in plumbing lines.

Clerestory

A window above eye level that admits daylight.

Climate

COLD…minimum envelope/cubes/big sloped roof, glass on south, storage & kitchen to north, tree shield, Salt Shaker
TEMPERATE…stretch e-w, porches/awnings, deciduous trees s-w, pines north
HOT HUMID…detached kitchen, ext passageways, balconies, breezeways, elevated, use Thermosiphoning
HOT ARID…greatest daily variations…high thermal mass mtls, atrium, courtyard, small high windows, fountains

Closed Loop

Type of active solar system that uses one medium for collector (glycol – antifreeze),  which then runs thru (but doesn’t mix with) water system.

Code

Organized body of rules and regulations adopted and enforced by a governmental unit.

• Prescriptive Codes: (i.e., ASHRAE 90)  Specifies sizes, materials, design strategy

• Performance Codes: (i.e., BEPS) Only specifies how much energy can be used

Coefficient of Performance (COP)
(congruent to EFFICIENCY)

Ratio of the amount of heat energy delivered by a heat pump  - to - the amount of energy removed by a refrigeration machine – to –
The amount of energy expended in the removal.   Relates to efficiency, and often exceeds 100% - as in 2.7 for a heat pump.

Coefficient of Utilization (CU)

Ratio of useful light arriving at the work plane – to – amount of light emitted at the source.  ENERGY DELIVERED vs. ENERGY USED.  CU depends on reflectivity of different surfaces and aspect ratios of ceilings, walls, and floor cavities, and direction of lighting.  Common CU values are .5 to .8.  CU is used in the ZONAL CAVITY METHOD.  What are key components to do this calculation?

Coefficient of Heat Transmission (U)

Composite coefficient of an assembly of materials in a structure.  U=1/sum R  
LOW U = HIGH INSULATION VALUE

Cold Air Register

Open plate between 2 floors, allows cold air to move between spaces while preserving visual privacy

Color Rendition Index (CRI)

Measure of how well light displays true color.  Scale of 1-100 (100=best color)

Color Temperature

A way to rate white light (red hot, white hot)

Combination Standpipe

Required for buildings over 150’ tall @ every stairwell, or smoke-proof tower.  Has 2-1/2” outlets for firemen, and 1-1/2” hose rack for occupants.

Comfort Zone (Range)

Combination of thermal and environmental conditions within which more than 50% of humans are comfortable.  Shown on a psychrometric chart.  In US – comfort zone is 65F to 78F, and 25% RH to 75% RH.

Commission Internationale d’Eclairage (CIE)

European agency that endorses the daylighting strategy called DAYLIGHT FACTOR METHOD.

• Assumes overcast and diffused skies

• Often used for computer calcs

Compartmentation

Spaces used by different occupancies are separated by fire rated assemblies of 1-4 hour ratings.

Compression Refrigeration Cycle

CONDENSER sends hi pressure/med temp liquid to EVAPORATOR
EVAPORATOR boils it and sends it off to COMPRESSOR as a low temp/low pressure gas

Condenser

Part of refrigeration cycle that CONDENSES heat OUT of FREON, releases latent heat, which warms water or air.
Pump increases pressure of FREON; it condenses, and releases heat.

Conduction

Heat transfer that occurs when objects are in direct contact.  Not directional.  Heat energy flows from hot to cold.

Conductors

Wire, cable or busbars that carry electrical current. They range from 16 gauge (.05 inch diameter) to 4/0000 (.46 inch diameter).  One insulated 6 gauge or larger, or several smaller ones bound together, is called a cable.  8 gauge or smaller is called wire.

Conductance (C)

“C”.  Rate at which a specific thickness of a given material conducts heat thru direct contact between molecules.  Occurs when there is a temperature differential within the material.  Rate of heat transfer is directly proportional to temperature differential.  Each material conducts heat differently.  Reciprocal of Resistance.

Conductivity (k)

A property of every material, the inverse of resistivity (r value)
LOW K = HIGH INSULATION VALUE

Cones

1 of 2 nerves in RETINA – senses color – requires much light to function.

Constant Volume

Fan Coil System can heat and cool simultaneously but not in same zone – efficient – constant volume of air from a single duct – H/C at each zone.

Construction Type

Determines fire resistance.  TYPE 1=most fire resistant, TYPE 5 = least fire resistant (ordinary wood structure)

Cooling Load Temp Differential

Q etd = v(A) ETD    q cltd = v(A) cltd  READ page 1-18

Cooling Tower

A/k/a EVAPORATOR   Dissipates heat into air (heat and moisture) Requires addition of water

Copper Tubing

Best material for supply piping.  Doesn’t rust, resists corrosion, thin walls, Type K, L, M (M = thinnest)  Joined via soldering.

Conduit

Connections

Wye or delta

Convection

Transfer of thermal energy thru a fluid medium (liquid or gas). Only heat transfer that is strictly DIRECTIONAL. Heat transfer that occurs when a warm fluid rises, displaces cold fluid, which then falls.

Conveying Systems

Elevator Types (pros/cons)
Escalator Types (pros/cons)
Elevator Safety Equipment
Lobby signaling equip?

CLTD (or ETD)

Cooling Load Temperature Differential (same as Equivalent Temperature Differential)
Approximates the effect of radiation and conduction.  Based on wall mass, orientation, color.

CU Factor

Ratio of useful light arriving at the work plane – to – amount of light emitted at the source.  ENERGY DELIVERED vs. ENERGY USED.  CU depends on reflectivity of different surfaces and aspect ratios of ceilings, walls, and floor cavities, and direction of lighting.  Common CU values are .5 to .8.  CU is used in the ZONAL CAVITY METHOD. 

Crack Method

Measures infiltration.  Based on total # linear feet of cracks and joints around doors and windows.  A table that accounts for wind speed and opening type determines amount of leakage.
Qcfh = LF x Cfh/lf

Critical Distance

Max length of drainpipe between a trap and an air vent.  Can be no more than 48 times the pipe diameter.

Current

Flow – water measured in gallons per minute, electricity in amperes

Cycle

Complete set of repeating events, as in alternating currents or sound.

Cycles per Second (CPS)

Measure of frequent in electric current or acoustics…# of cycles/sec of a wave or oscillation.  In acoustics, term used is HERTZ (“Hz”).

Dampers

Balancing Dampers – regulate flow of conditioned air
Motorized Control – remote systems that vary airflow within an automated control system
Splitter Dampers and Turning Vanes – prevent airflow resistance due to corners in the ductwork.
Fire Dampers – stop airflow automatically in case of fire.

Darrieus

Type of VAWT (vertical axis wind turbine), resembles an eggbeater.  Very efficient, cannot self start.

Daylight Factor Method

1 of 2 daylighting strategies to calculate amount of daylight in a room:

• Assumes overcast and diffused skies

• Often used for computer calcs

Daylight

Diffuse light source with perfect color rendition.

Daylighting

Use of natural outdoor light to replace or augment electrical indoor light.  Produces energy savings.
Daylighting a Room:
Depth of penetration of usable light = 2.5 H (H=head height of window AFF)

dBA

Decibel measured in the A scale, which is weighted to account for the sensitivities of the human ear.

DC Motor

Used for small scale applications and ELEVATORS.  Continuous and smooth acceleration to a high speed.

Dead

Spaces with short reverberation times (absorptive surfaces)

Decibel (bB)

Logarithmic measure of sound intensity.  Named after Alexander Graham Bell.
(x) IL=10log I/Io
IL=intensity level in decibels
I=intensity of sound heard (Watts/cm sq.)
Io=minimum reference intensity (lowest sound heard w/human ear)

Declination Angle

Tilt of North Pole in relation to sun, not affected by time of day.  AFFECTED BY TIME OF YEAR.

Deck Temperature

Temperature of air as it leaves the equipment room.

Degree Day (DD)

Amount by which the average outdoor temperature at a particular location is below 65 degrees F for one day.  DD are summed and stated for a month or year, and used to determine fuel needs and size mechanical equip. Measures temperature over time, against a reference temperature (65F).

Deluge System

Used in areas of high hazard.  All sprinklers open fully – pipe is empty until activated by a temp or heat sensor.

Delta Connection

Method of connecting windings on a three-phase transformer, end to end, which results in a triangular shape.

Demand Surcharge

Charges associated with peak demand on a building’s power use.

Design Day

The temperature of a theoretical day hotter or colder than 98 % of the days experienced in a given location.  Allows for the proper sizing of equipment to handle 98 percent of the temperature conditions.

Dew Point Temperature

Temp. of air at which the water contained in the air begins to condense and form dewdrops.  As temp drops, vapor condenses. Depends on dry bulb temperature.  Dew point is reached at 100% relative humidity, when DB and WB temps align.

Diffuser

Device through which the air from a duct (or light from a fixture) enters a room.

Diffusing

Surface is DIFFUSING if it doesn’t maintain an image.

Direct Current (DC)

Current that maintains a constant direction and constant voltage.
Used in low voltage applications.  More energy efficient than AC motors.

Direct Gain Space

Room where structure and thermal mass are in direct sunlight.

Direct Normal Intensity (Idn)

Where a hypothetical receiving surface is perpendicular to the solar vector.  Varies with time of day.

Distribution System

Delivers treated air/water to necessary zones.

Diurnal

Day to Night to Day
Solar energy arrives in seasonal AND diurnal cycles.

DDC

Direct Digital Control (find diagram)

Domestic Hot Water

Refers to potable water used by occupants for washing, cooking, consumption. Can be effectively heated by active solar systems.  

Doppler Effect

Change in sound wave frequency due to change in distance from source, or receiver, or both.

Downfeed System

Rooftop water-supply system used in tall buildings, where water flows by gravity.  Adds weight to roof, requires expensive structural engineering.  Upfeed system serves the lower floors.  Pressure determined by roof height and depth of water.

Drains to empty solar collectors when temp drops:

• Drain back     Senses temp difference and open valves to drain lines

• Drain down    FAILSAFE METHOD – collector is only full when pump is running.

Drainage Lines

Vert, and horiz. Branches of a pipe that carry waste water form fixtures to disposal point.  Soil pipes connect to urinals and water closets (toilets); all other are waste lines.

Dry Bulb (DB)

Temperature of air as read on an ordinary glass thermometer.

Dry Pipe Sprinkler/Standpipe

Systems whose pipes are pressurized with only air, invulnerable to freezing temperatures.  When actuated, air is vented and pressure forces water thru the system.

Duct Insulation

Dual Duct

Can heat and cool simultaneously – using an air-mixing box. 

Duct sizing

Depends on design velocity, supply volume, available space, required noise levels, and friction.

Economizer Cycle

Energy saving strategy in which a part of the HVAC system is shut of while the rest is used, such as shutting off the refrigeration when the outside air temperature is low, while the fan continues to operate.

Ecosystem

Ecosphere – 5 miles of earth’s crust
Biosphere – 5 miles of earth’s atmosphere

Effective Temperature

A measure of THERMAL SENSATION, not actual thermometer temperature. Fictitious temperature having the same physiological effect as air of a standardized temperature, humidity and velocity.  Measure of a comb of several comfort indexes:  dry bulb temp, relative humidity, radiant energy and convection.  Combination of dry bulb temp and MRT.

Efficacy

Ratio of the lumens emitted by a lamp to the electrical power (watt) consumed by the lamp.  Measures energy efficiency.

Effluent

Liquefied sewage that flows from a building’s disposal system into public sewer system or leach field or septic tank.

ELECTRIC heater

100% efficient

Electrical service entrances

Electrical Magnetic Tubing (EMT)

Thinnest of all metal conduits.  Galvanized, connections via special clamps. A/k/a THIN WALL

Electromagnetic radiation

Light is the part of the electromagnetic spectrum that is perceived by the human eye.

Electrostatic Filter

Cleans air – expensive – 2 charged plates which collect dust particles – rinse and replace

Electrical disconnects

In a resident, located on the main panel…usually used for high voltage.

Electrical Outlets

Single, duplex, waterproof, special purpose, triplex, clock hanger, combination gang, etc.

Electrical HVAC

Simplest HVAC to install and operate.  No space needed for pipes or ducts, and temp can be controlled with a separate thermostat in each room.  Electricity is most expensive energy source.

Electrical Current

The flow of electrons through a conductor.  Measured in amperes, which is the quantity of electricity in an electric current.

Elevators

Geared…used below 500 fpm
Gearless…quieter, longer life, efficient and low maintenance. WTC type applications
Electric
Pneumatic…vacuum pressure
Hydraulic…cheaper, slower, has a pit, uses a plunger at bottom of car (can be telescoping, or plunger-less)
18 sec wait time in an elevator lobby

Emergency Lighting

Required for all exits and certain critical functions – must have it’s own power source.

Emergency power source

May be provided by a separate generator or battery pack.  NO LEAD BATTERIES ALLOWED. Can use nickel cadmium batteries. 
Fluorescent lights don’t operate on 12v DC current, and require a transformer and invertor.

Emissivity (E)

The ability/rate at which material absorbs and then emits radiant energy.  Measured from 0.1 to 1.0, where 1.0 is the emissivity of a perfect black box at the same temperature.  Usually equals absorptivity (a) for any given wavelength.

Embodied Energy

Indication of how much energy must be invested to mine/harvest/transport/refine a unit of building material. 
Function of:

• Material’s availability

• Distance between raw resources and refining station

• Fuels used to refine/reshape material

Energy Codes

2 types:

• Performance Codes

• Prescriptive Codes

Enthalpy

Sum of sensible plus latent heat stored in the air or a material.  Also known as Total Heat. Not affected by air movement.

Equinoxes

Occur in Fall and Spring.  Sun/Earth position midpoints when angle of declination = 0 degrees

Equivalent Circular Diameter

Way of specifying duct size: the circular dimension that results in the required duct cross section.

ETD (or CLTD)

Equivalent Temperature Differential (same as Cooling Load Temperature Differential)
Approximates the effect of radiation and conduction.

Equipment

Generates heat = qm = 1500 x Bhp    (Bhp = Brake Horsepower)

Equivalent Spherical Illumination (ESI)

Optimum illumination – with all shadows and reflections eliminated.  (Imagine a sphere of light surrounding an object.)

Escalators

Safer than stairs
Handle more traffic than elevators
Come in standard widths (32’ and 48”) and incline (30 degrees) and speeds (90 or 120 feet per minute)
Not always installed in pairs.

Eutectic Salts

Evaporate or freeze in H2O – used in solar collectors (also paraffin is used)

Evaporator

Part of a refrigeration cycle – FREON passes thru constrictive/expansion valve – causes a pressure drop downstream.  Liquid evaporates and absorbs latent heat.  Water/air is cooled.

Evaporative Chiller

Uses latent heat of evaporation to transfer heat to atmosphere.  A/k/a COOLING TOWER – typ located outside of a building

Exit

Continuous and unobstructed means of egress to a public way.

• Minimum width is generally 44 inches.

• Most buildings require 2 or more exits.

• All spaces must be within 150 ft from an exit. (200ft if sprinklered)

• Divide total floor by 50

• Doors swing in direction of travel, equip w/panic hardware

• Consider ADA egress (ramps, areas of refuge)

• 5+ stories = 2 hr rated stairwells, all others = 1 hr rating

• 7+ stories = one stairwell must be Smokeproof (open air vestibule)

Exit Lights

Require separate generator/nickel cadmium battery pack (no lead batteries!) – fluorescent lights do not run on 12volt DC current, so need a transformer and invertor.  Exit signs require 2 sources of illumination

Extinguishing Equipment

Automatic and handheld types.  Halon 1301 or 12211 used for Class B & C.  Carbon Dioxide can be used if equipped with a loud alarm system.  Both systems are good for areas containing documents and art. Halon is used for computer rooms.

Fan Coil System

One of the most efficient ways to simultaneously heat and cool.

Fan Sizing

Size to move volume of air thru duct to farthest diffuser @ required flow rate, overcoming friction.

Fiber Optics

Fibrous Filter

Common for furnaces – removes dust and lint – needs to be replaced often.

Filament

Inside a bulb/lamp – often made of tungsten alloy – pass an electric current thru it to produce light and heat.

Filters

HEPA filter is most economical

Film Coefficient (fi)

Thin film of air that occurs next to a wall.  Provides a resistance.  Calculated as the inverse of (fi).

Fins

Stops direct sunlight – on south walls, use horizontal fins; on e&w walls, use vertical.  May combine systems as needed.

Fire Assembly

Complete fire-resistive assembly consisting of a fire door, fire damper, or fire window and it’s mounting frame and hardware.  Entire assembly is labeled and approved by a testing agency – rated at ¾, 1, 1-1/2 and 3 hours.

Fire Detection

• Ionization Detectors…respond to POC at earliest stages (ticked by kitchen smoke and cigarettes)

• Photoelectric Detectors…respond to visible smoke

• Temperature Sensing Detectors…less sensitive, features a fusible link or electric alarm

Fire Codes

3 goals:

• Afford protection for escape of occupants (place of refuge or evacuation)

• Insure sufficient structural integrity so fireman can fight fire

• Allow building to survive fire

• 4th goal is fire prevention

Fire Sprinklers and Finishes

Escutcheons & cover plates are cosmetic, variety of finishes or painted.  Sprinkler head can’t be painted or it’ll lose fire detection sensitivity.

Fire Suppression System Parts

Water supply, check valves, fire dept. connections, local alarm, bulk main, cross main, detectors, branch lines, sprinkler heads

Fire Classifications

Type A – involve ordinary materials like wood, cloth, rubbed and paper (extinguish w/water)
Type B – involve flammable liquids and gases
Type C - electrical fires that must be extinguished by non-conductive means (halon)
Type D – Combustible metals requiring special extinguishers

Fire Compartmentation

Means of containing fire, heat, smoke and toxic gases.   Provides place of refuge for occupants & firefighters by dividing building with fire barriers.  Comprised of special floor, wall and ceiling assemblies.

Fire Damper

Automatically stops airflow in case of a fire.

Fire Resistant Ratings

5 construction types:
Type 1 – Most fire resistant
Type 5 – Wood stud construction
Refer to UBC chap 18-22

Fixture Unit

Unit of liquid flow used in sizing both supply and drainage pipes.  Defines probable demands on plumbing fixtures.  One FU = a unit flow rate of one cubic foot per minute.  Relationship between gpm and FU is not constant

Fixtures

Know light patterns each casts

Flanking Paths

The path sound takes around, instead of through, a partition.  Flanking paths include floors underneath walls, ceilings, pipes, air ducts, doors and electrical conduits.

Flashover

Gases accumulate at ceiling, overheat and explode.

Flat Plate Collector

Active solar system – form of a flat plate – tilted to the right ALT and AZ to collect majority of sun’s direct rays.

Flexible Metal Conduit

FLEX – or – GREENFIELD
Available w/ and w/o a flexible waterproof jacket. 
Cannot be used underground.

Flame Spread Rating

Numerical classification indicating the rate at which flame will spread in/on a given material.  Higher #s flame up more rapidly.

Flame Detector

Fire alarm system sensitive to infrared and ultraviolet radiation.  Most rapid type of fire protection.  False alarms are frequent, cannot detect smoke.

Flexible Metal Conduit (Flex)

Can be used anywhere except underground (no exterior uses).

Flow Rate

Greater the flow rate, the greater the friction at a given diameter.
Smaller diameter pipe, the greater the friction at a constant flow rate.
Friction loss is function of flow rate and pipe diameter.
Devices in the line add friction.

Flue

Exhaust device vent the byproducts of combustion.

Fluorescent

Efficient lighting system based on passing current thru gasses inside a glass tube.  Transformers needed to get current to arc thru gas at 110 volts, and ballasts required to control the voltage (noisy – A-E rating , A=quietest).

Flush Valve/Flushometer

Valve that releases definite amt of water into a plumbing fixture each time it’s activated. High speed for short time – used in tankless toilets.

Flux (F)

The rate of flow of lumens or watts thru a theoretical surface. (@1sf from 1 cp, the light flow = 1 lumen)

Focusing Collector

Parabolic trough or dish or arrangement of lenses that moves/focuses light onto a tube or point.  Generates much higher energy densities and temperatures than a flat plate collector.

Foot Lambert (fL)

A quantitative unit for measuring brightness as reflected from a surface.  Measured in Lumens per SF.
A perfectly reflective surface exposed to one footcandle would have a luminance of one foot Lambert.

Footcandle (fc)

Measure of illumination equal to one lumen.  Amount of luminance from one lumen on a one square foot work surface.

Forced Air Systems

Heating/cooling system that uses a fan to circulate treated air thru ducts to occupied spaces.

Forced Air furnace

Duplicates the boiler in residential applications.  Air comes in thru a manifold inside a combustion chamber – manifold is warmed by gas, oil, or propane and in turn heats surrounding air.  Combustion air is vented thru a flue, treated air is distributed to necessary areas.

Four Pipe System

Hot and chilled water system having separate return lines for each supply, and no mixing of the two streams.

Four-way

3-way switches are 2 switches controlling on fixture. When more than 2 switches are necessary, 2 must be 3-way and the remaining are 4-way.

Forced Convection

Movement of a fluid by fan or pump in order to force heat exchange.

Formulas

Conductance=C=1/R
Amperage= I=V/R
Resistance=R=1/C
Voltage= V=IR
Sound Intensity= IL=10 log (I/Io)
Intensity Levels= E=I/d squared

Freon

A family of several chlorofluorocarbons or CFC gases, circulated in a closed refrigeration loop.

Frequency

# of cycles occurring per second, in alternating current or acoustics.  In acoustics, frequency determines the pitch.

Fresh Air Intake

Opening which supplies clean fresh air to HVAC system.  Locate intake away from cooling tower and other exhausts.

Fresnal Lens

Uses less material than a normal lens – most common application is a car headlight.  Faces are ridges to help focus and direct light.

Friction Loss

Expressed in inches of water per hundred feet, also known as STATIC HEAD. 
One pound of pressure is required to support a one-inch column of water.

Frosted Glass

Example of translucent material – no image passed thru – only light.

Frost Line

The max soil depth at a given location that is expected to freeze in cold weather.  Water piping must be buried below this level.

Fusible Link

Paraffin or wax which melts at a predetermined temp, setting off a sprinkler head, alarm system or activating other fire protection devices.

Fuse

Devices composed of a soft metal link in a glass plug or fiber cartridge – rated at a certain current flow.  If current is exceeded, metal link will melt, breaking the circuit.   Largest glass plug is rated at 30 amps, cartridge fuses go much higher.

Galvanized

Thin layer of zinc applied to steel – bond makes metal relatively rust-resistant.

Gate Valve

Intended to be entirely ON or OFF.  Minimum restriction when fully opened, but causes lots of turbulence when partially open.

Gas Piping

Usually run in untreated steel (black iron) pipe.  Can be run in plastic in some applications.

Gas mounting heights

Carbon Monoxide (CO) – at breathing level (4-5 ft AFF)
Heavier than air (propane, LP, refrigerants) – one foot AFF
Lighter than air (methane, natural gas, hydrogen) – one ft. below ceiling

Doctors’ Office uses CO, O2/methane = use a ball valve

Generator

Rotating a wire loop between two magnetic poles creates a current.  Basic principle behind a GENERATOR. 
A generator converts mechanical energy into electric energy.  (a motor converts electric energy into mechanical energy.) 

Geothermal Heat Exchanger

Consists of water-filled pipes belowground, in contact with temp stable earth – absorbs heat via conduction (pipes to earth) for use in building.

Glass

High transmissivity in the visible spectrum (short wavelength)
Low transmissivity in the infrared spectrum (long wavelength)
Factors combine to cause Greenhouse Effect.

Glare

Extreme contrast between bright and dark that interferes with vision.
DIRECT GLARE: brightness in the field of vision
INDIRECT GLARE: brightness reflected from other surfaces

Globe Valve

Turn water ON and OFF and METER or THROTTLE flow at intermediate rates.  Restrict flow even when wide open.

Globe Thermometer

Measures Mean Radiant Temperature (MRT) – temperature of air and average of all surrounding surface temperatures.  Human Comfort.

Gradient

Layers of heat energy at each component of an assembly

Gravity Feed

Convection moves heat from a manifold UP to the rooms.

Greenhouse Effect

Radiant heat gain thru glass.  Also called INSOLATION.  Visible light enters a space, reradiates in infrared spectrum which is trapped by the glass.  On a global level, carbon dioxide in the atmosphere cause global greenhouse effect.

Grey Water

Used water from sink, tub and shower lines.

Ground Fault Circuit Interrupter

(GFCI) Outlet receptacle used in wet areas to protect against electric shocks.   Required when outlet is within 6 feet of water source.

Ground

Electrical conductor connected to the earth or to a pipe extending into the ground.  Dissipates hazardous currents to the earth.

Halon

Gaseous fire extinguishing medium that smothers fire, used in automatic systems in computer rooms.

Handicapped Access

Toilet stalls – 60” clear at 10” above floor, 19’ seat height, grab bars, 33’ doors
Sinks – tilt mirrors, lever controls – 32-36” aff
Drinking fountains – 2 heights:  36-39 for able bodied, 32-36” aff for wheelchairs
Showers – 33’ doors, no lip, 19’ seat, grab bars, 60’ diameter at 10” aff

Hard Water

Caused by deposits of calcium carbonate and magnesium in metal pipes.

Hazard Levels

Use to determine possibility of combustion:

• Light – churches, hospitals, offices, homes
• Ordinary – 1.garages, laundries   2. Libraries, stacks, printers      3.paper plants, tire mfgrs.
• Extra Hazard – aircraft hangers, explosives plants

Heat Activated Sensors

Less sensitive type of detector, uses a fusible link.

Heat Detector

Fire alarm system that senses heat.  Reliable and cheap, but takes time for heat build up to occur before reacting.  Does not respond to smoke.

Heat Energy

Flows from hotter to cooler object (high pressure to low pressure).  Can be transferred w/o a change in temperature (melting ice cube=latent heat). Latent heat causes a change in state.  Sensible heat causes a change in temperature.

Heat Loads in a Building

Caused by People (450 BTUs at rest, 2500 BTUs at heavy activity), Lighting, Equipment, Solar Gain

Heat Pump

• Based on refrigeration loop used to bring heat into a space instead of removing it from space.  
• Reversible system that changes refrigerant flow by using the evaporator as a condenser, and vice versa.
• Most efficient in a moderate climate. Can be used to ventilate.
• Can be an entire system of such units attached to a recirculating heat sink.
• Outgoing an incoming air on kept separate, transfer heat as needed.

Heat Transfer Processes

Conduction…surfaces touch, depends on surface temperatures
Radiation…heat radiates to cooler surface, depends on surface temperature and orientation to body (heats OBJECTS)
Convection…fluid medium transports heat, depends on air temperature, motion and humidity. 
Evaporation…evaporated liquid removes heat from surface it leaves, depends on humidity, air motion and temperature.

HEPA Filter

High efficiency particulate air filter.  Removes dust and tiny particles from moving stream of air.

Hertz (Hz)

Unit measure of sound frequency, or Alternating Current – number of cycles per second of a sound wave.  Named for physicist Heinrich Hertz.

High Intensity Discharge (HID) Lamps

Family of lamps consisting of a quartz envelope inside a glass envelope.  The inner quartz tube can stand higher temperatures, and allows for the current to arc between two electrodes exciting plasma of mercury, metal halide, or high-pressure sodium.
4 types:
MERCURY VAPOR – clear bluish light – 50 lumens per watt – 24,000 hour life
METAL HALIDE  - 80 lumens per watt – 10,000 hour life
HIGH PRESSURE SODIUM – HPS – most efficient – 110 lumens per watt – 24,000 hour life – poor color
LOW PRESSURE SODIUM – highest efficacy and life – but yellow monochrome color – used for parking lots.

BULB RATINGS:
Incandescent (lowest rated)
Tungsten halogen
Mercury vapor
Fluorescent ties with metal halide
High pressure sodium (highest rated)
Low pressure sodium  (limited application)

High Pressure Sodium (HPS)

Most efficient of the architectural HID lamps…110 lumens per watt – 24,000 hour life – poor color

Horizontal Axis Wind Turbine (HAWT)

One of 2 basic types of wind turbine: vertical axis and horizontal axis.
More common type in use today, available in leading (blades are upwind) or trailing (downwind) blade configurations
Leading requires a tail like a weather vane, or a wind-sensing device.
Trailing results in eccentric vibrations.

Human Comfort

Humans generate between 450 and 2500 Btuh.
Cold weather we radiate, conduct, evaporate and convect heat.
Hot weather we evaporate.

Hydrofluorocarbon

Alternative gas to CFC being investigated for use in refrigeration.

Hydronic Systems

Water mechanical system used only for heating (a/k/a Radiant System).  Sometimes combined with forced air systems.

Hydroscaping

Plants acclimated to high moisture situations (lily pads)

Hydrogen

High-grade fuel

HVAC

Relative Costs:
$$$$ Fan Coil
4 pipe Hydronic system – h&c simult.
$$$ VAVS
single duct w/variable volume (zoned)
$$ 2 Pipe Hydronic System 
heat only, boiler w/ supply & return pipe
$ Single Duct Constant Volume
(h&c)

Heating, Ventilation, and Air Conditioning
Consists of a PLANT (creates cool/warm air) & a DISTRIBUTION (delivery) SYSTEM

Boiler…heated tank or exchanger tube (normal boilers/furnaces run @ 80% efficiency)
Flue...vents byproducts of combustion
Forced Air Furnace…uses fans to move air past a heating manifold
Cooling Tower = Evaporative Chiller
Blowdown Valve = used to drain out debris and dirt from cooling tower
External Combustion Air…brought in from outside

Refrigeration:
Freon…a family of CFC gases, pressure changes within the loop cause temp changes

Heat Exchanger Coils:
Condenser…increased pressure condenses freon gases, releasing latent heat of evaporation (warms Freon, cools Air)
Evaporator…drops pressure, liquid is released, absorbs latent heat from surroundings (cools Freon, warms air)
Condensation at high temps (loses heat)/evaporation at low temps (absorbs heat) – moves heat from hi to low temps
Different systems?

HP or BHP

Horsepower or Brake Horsepower, a unit of power, roughly equal to 746 watts.

IES

Illumination Engineering Society

Illumination (E)

The intensity of light falling on a surface, usually expressed in footcandles.  (E=F/A   or Illumination = Flux/Area) 
E=I/d squared

Impact Isolation Class (IIC)

A rating of the degree of isolation of a floor against the transmission of impact noises.

Impact Noise

Erratic sounds caused by footfalls, dropped objects, vibration of mechanical equipment, etc.
Resultant sound radiates from other locations.

Incandescent

Generates more heat than light; in direct proportion to the wattage.  Contains a filament (tungsten alloy) that heated by electricity and glows.  Least efficient bulb.  Short lifetime (2000 hrs.)  Output = 15 lumens per watt.  Sized by wattage in 1/8” diam multiples.

Incipient Stage

1st stage of a fire when invisible products of combustion go off.  Detected at this stage by an IONIZATION fire detector.

Indirect Gain

Similar to direct gain space, only thermal mass is not in direct sunlight area of the room (in shade).  Heated by reflected sunlight or warm room air.

Infiltration

Sensible heat loss or gain (qv) due to unintentional ventilation.  q=Vx1.08xDeltaT (v=ventilation, Delta T is temp change)
Measured by the CRACK METHOD or AIR CHANGE METHOD.

Insolation

Greenhouse effect – radiant gain thru glass – a form of radiation.

Insulation

Specified by R-value.

Intelligibility

Sight lines mirror hearing lines.  Reflected sound should arrive at listener at nearly the same time as the sound from the source.
Length of reflected sound path should not exceed length of direct path by more than 34 feet.

Intensity (I)

Amount of light put out by a source, measured in candlepower.

Intensity Level (IL)

Intensity of sound at a given location, measured in watts per square meter – or more commonly in dB where the reference level is 10-12 watts/meter2 or 10-16 watts/cm2

Interceptor

a/k/a  SEPARATOR.  Box-like device that prevents passage of oil and debris into the sewer drainage system.  Require periodic servicing and must be accessible.  Different from a trap.

Interlocked armored cable BX)

Prewrapped set of wires encased in an interlocking metal armor.  Factory assembled, called BX cable.  May not be embedded in concrete or laid underground.

Intermediate Metallic Conduit (IMC)

Steel conduit with thinner walls than plumbing pipe, slightly less expensive and generally acceptable for conduit as rigid conduit.

Interstitial Space

Area between ceiling and floor above.  May be used as a return air plenum in some instances.

Inverse Square Law

E=I/d squared

Physical principal that states the intensity of a phenomenon is inversely proportional to the square of the distance from the source to the measuring device.  True for point sources of light, and for sounds in an open field.  Further away, much reduced effects.

Illumination = Intensity/square of the distance from source

Inverse Square Law

Applies to sound and light intensity, which is inversely proportional to the square of the distance between the source and receiver.
DOUBLE THE DISTANCE, reduce dB by half.

Invert

Lowest point of the inside of a drain, pipe, channel, or other liquid-carrying conduit.

Ion Exchange

Process of water softening in which calcium and magnesium ions are replaced by sodium ions.  A/K/A the ZEOLITE PROCESS.

Ionization Detector

Fire detector that senses products of combustion (POC) emitted into the air during incipient stage of a fire.  Very sensitive, expensive, may cause false alarms.  Used for spaces with high combustion hazards and electrical overloads.

I=V/R

Ohm’s Law

Relates 3 basic factors in electricity – potential (volts), current (amps), and resistance (ohms)

• I= current , measured in amps
• V=voltage, measured in volts
• R=resistance, measured in ohms

Kelvin

Heat scale – Sun is 6000 degrees Kelvin

Kilowatt hours (kwh)

Thousand watts per hour

Kilowatt (KW)

Unit of electric power equal to 1000 watts.

(k)

Symbol for thermal conductivity.  Ability of a material to transmit or conduct heat or electricity.  Amount of heat transmitted in 1 hour thru 1 sf of 1 inch of the material. Expressed in BTUs.

K Factor

Thermal conductivity of one SF of a material per inch of thickness, with a surface temperature difference of one degree F.

KVA

Rating for transformers equal to the product of volts and amperes divided by 1000.  The product of the KVA and the power factor gives the power in kilowatts.

Latent Heat

Heat energy that causes a change of state, such as ice to water.  Air condensation causes a heat-energy reduction.  Transfer of heat energy is not TEMPERATURE, which is a measure of heat.  Heat added to or removed from a substance when it changes its state:

• Latent Heat of Evaporation (sweat)
• Latent Heat of Fusion (freezing)

Leach Field

Wastewater treatment system that uses a grid of perforated pipe, laid in shallow trenches with loose gravel.  Wastewater seeps into the soil, where it oxidizes and decomposes via bacteria.

LEDs

Light emitting diode, can be used as a light source.

Lift

1 psi can lift a column of water 2.3 feet high.
Total lift to get water to fixture, add additional lift for fixture function and friction.

Limestone (CaCO3)

Can be dissolved into ground water and cause hardening, and deposits on pipes.

Light Shelf

Shelf constructed below a window, designed to reflect light up towards a ceiling and distribute it back in space.
Also an overhang (inside or outside or both) used with a clerestory to reflect light up to a ceiling and reduce direct light adjacent to window below.

Lighting Lamp Types

Least to most efficient:

High Intensity Discharge (HID) = Mercury Vapor/Metal Halide/Hi-Pressure Sodium/Low-Pressure Sodium
All HID lamps require delay of 1 minute or more to resume normal levels after a power interruption.

Light

Ambient
Diffused
Direct
Semi-Direct
Presents a heat load = ql = 3.4 W (wattage)

Lighting Illumination Levels for Occupancies

Kitchen/office 500-1000 lux
Passageway 50-100 lux
Dining 100-200 lux
Bathroom/laundry 200-500 lux

Lighting Ballasts

3 functions in a fluorescent/HID lamp:

• supply controlled voltage to heat lamp filaments
• start lamp by striking an arc
• limit lamp current

Light levels in an elevator

Light Intensity

Quantity of light generated by a source.  Measured in terms of candlepower (CP)

Lithium Chromide

Absorbs moisture, can be used in heat/moisture exchanger

Live Space

Space where sound waves reverberate due to reflective surfaces.  High ratio between direct sound and reflected sound = more live space.

Logarithmic Scales

Acoustics uses logarithmic scales.
IL = 10 log (I/Io)
IL = intensity in dB
I= intensity of sound being measured
Io=reference intensity of 10 (-16) --- the quietest sound we can hear.

Low Pressure Sodium

Highest rated lamps in lifetime and efficacy. Yellow light, often used in parking lots.

Lowboy

Small furnace approx. 5 feet tall.

Lumen

Unit of luminous flux that is a measurement of the total output of a light source. 

Equal to amount of light flowing thru one sf of surface area located one-foot form a one candlepower source.

Lumen Method

1 of 2 methods for calculating daylight needs.  Calculate in 3 room locations (5’ from window, middle of space, 5’ from back wall.  Can calculate daylight from 1 (or 2 opposite) window wall (s) – but not a corner window.

Luminance

Measured quantity of light at a given point on a surface coming from a given direction.  This measure accounts for the reflectance and transmittance of materials.

Luminaire

Complete lighting system consisting of a light source, reflector, refractor and all parts necessary for the fixture, housing and power supply connections.

Lux

Unit of illumination based on the metric system.  Equal to 1 meter-candle or 1 lumen/m2.  In the US – 1 footcandle = 1 lumen/ft2

Loss of Life?

Magnesium

Mineral that causes hard water.  Occur at 150 ft intervals, and where a new line joins an existing one.

Makeup Air Handling Unit (AHU)

AHU designed to supply 100% outside air to a space, replacing air lost thru exhaust fans or building envelope.

Manholes

Similar to cleanouts, for pipelines 10” in diameter or more.

Mass Wall

Thermal collectors, often behind a glass skin.  Store heat energy w/o rapidly raising indoor temps.  Trombe and Water walls are examples.

Mass Law

Theoretical law that states that for each doubling of mass in a wall, there is a 6bD drop in the actual amount of sound transmitted.  In actual practice, it’s closer to 5 dB.

Maximum Solar Gain

Occurs in Summer solstice

Mean Radiant Temperature (MRT)

A/k/a OPERATIVE TEMP (top)

The average temp of all radiating surfaces w/i line of sight of a body.  Measured w/ a globe thermometer & independent of air temperature.
Used to determine the Comfort Zone. 
If MRT is low, than comfort zone moves to higher ambient temps (and vice versa).

Measurements to calculate solar gain

Azimuth
Latitude
Altitude

MEP Costs

• Hospital = 40% of total project costs                           Vertical transportation = 10-15% of construction costs
• College classes = 30%
• Retail = 25%
• Mid Level Offices = 20%

Mercury Vapor Light

First of the HID lamps. Has green tint

Mixing Box

Part of a double duct system – component where treated air is combined at a ratio controlled by a thermostat to provide the appropriate temperature to a room.

Minimum Gauge Wire used in constr.

14 gauge copper wire.  Smaller number equals larger diameter.

Modulus of Elasticity (E)

Motor

Converts electric energy into mechanical energy.  (A generator converts mechanical energy into electric energy)

Multi-zone

Double duct or dual duct system - ideal for linear buildings with many different thermal conditions.

Nanometers

One millionth of a millimeter.

NEC

National Electric Code

Neutral

The wire or conductor in an electrical system that is equidistant in voltage from the phase conductors of the system.  NOT THE SAME AS A GROUND.

Nickel-cadmium

Expensive, rechargeable batteries good for emergency lighting back-up power.  Emit no fumes.

NFC

National Fire Code
Specifies details of fire protection systems.

Noise Criteria (NC)

Called the 1957 NC curves, offers ranges of values for different occupancies.
Single-number system – each curve represents a maximum sound pressure levels (SPL) level in dB for any given location, using standardized reference contours. The curves weight the frequencies to which the human ear is sensitive.

LOW FREQUENCY SOUND CAN HAVE HIGHER SPL THAN HI FREQUENCY SOUNDS.
As NC# decreases, max. SPL increases.

Noise Reduction Coefficient (NRC)

A one-number rating system giving the average sound absorption coefficient of a material at frequencies of 250, 500 1000 and 2000 Hz.

Occupancy

The purpose for which a building will be used.

• A=assembly
• B=offices, commercial
• E=education
• H=hazardous
• R=hotels & houses
• I= institutional
• M=garages

Occupancy Group

Designations for a group of several occupancies that have comparable fire safety considerations, and are grouped together by code.

Otis

Elisha Graves Otis - Invented an elevator safety device in 1853, later introduced the escalator in 1900.

OSHA

Occupational Safety and Health Act – regulates working conditions.

Ohm’s Law

(Analogous for water AND electricity)

Relates 3 basic factors in electricity – potential (volts), current (amps), and resistance (ohms)

Relationship between voltage, current and resistance in direct currents.  States that current (amps) in a circuit is directly proportional to the resistance (ohms).  One Ohm is the unit of measure of electrical resistance to the flow of current.

Higher V means more fixtures on same current. (?)

I=V/R

I= current , measured in amps
V=voltage, measured in volts
R=resistance, measured in ohms

Ohms

Measurement of electrical resistance

Open Loop

Means fluid going thru the solar system is fluid that will be consumed (domestic water).

Outlet

RECEPTACLE…placed no further than 12 ft apart in a residence.  All should be 3-prong (3rd prong is grounded).  Separate outlets in same room onto different circuits for redundancy.

Overall thermal transmission value (OTTV)

Weighted U value average for all exterior surfaces of a building.  Doesn’t account for solar design or site orientation – just the THERMOS BOTTLE concept (does it leak?)

Overhangs

Protect south facing windows from high summer sun, allows low winter sun to enter spaces.  Raise it high on wall, or tilt to match desired azimuth.

Oxidize

Copper pipes form a thin oxidation film that protects copper pipes from corrosion.

Panelboards

Set of fuses or circuit breakers that is the central distribution point for electrical loading in a building.

Panic Hardware

Door-latching assembly that will release the latch if a force not exceeding 15 lbs is applied to it. 

Passive Solar Design

Practice of orienting and sizing a building, its windows and its internal masses in such a way that it responds to the sun and to the climate, w/o using mechanical equipment.

Parking Lighting

1 footcandle required

Parallel Resistances

1 of 2 types of resistances in an electric flow path: SERIES and PARALLEL resistances.
Series resistance – R total = R1 + R2 + R3 etc
Parallel – 1/R total = 1/R1 + 1/R2 + 1/R3 etc

Peak Demand Surcharge

Charges associated with peak demand on a building’s power use.

Perception

Eye has sensing device (retina), focusing device (lens), brightness device (iris).

Performance Code

States what the final result needs to be and how it will be measured – does NOT specify how to achieve that result.

Perm

Unit of permeability for a given material – expresses the resistance of the material to penetration by water or water vapor. 
1 perm = flow of 1 grain of water vapor thru 1 sf of surface per hour (w/a pressure difference of 1” of mercury)

Permeability

Property of permitting passage of water or water vapor thru a material w/o causing rupture or displacement.

PH

Scale for measuring whether solution is acid or base.  0-6.9 = acidic, 7= neutral, 7.1-14=base (alkaline).

Phase change

A change of state – not a change in temperature (melting ice)

Phosphor

Used to line glass to affect light color.

Photoelectric Detector

Reacts to visible smoke in the air that blocks a beam of light.

Photovoltaics

Solar cells that create an electrical charge when exposed to light.  Equivalent to DC current battery, can be converted to AC.

Pipe Joints

• Plastic – connected with solvent/cement
• Iron/Steel – threaded connections
• Copper – soldered with flux

Piping designations

Polyvinyl dichloride (PVDC) - may be used for hot water piping (180 degrees F)
Metal piping – subject to electrolytic corrosion

Pitch

Humans perceive the wavelength of sound in terms of it’s PITCH.

Plant

Boilers
Chillers
Refrigeration cycle
Heat pump

Plant Placement

Cold – evergreens on N & NW, deciduous on East and South

Plastic Pipe

Prime competitor of copper pipe.  Available in 2 types:  PVC (white, used for supply) and ABS (black, used for drainage)
Does not corrode, but UV rays can deteriorate it – so do not expose outside or above ground.  A special GREEN plastic pipe is available for above ground fixtures.

Plenum

Area between ceiling and floor/roof – used as a huge slow-moving air duct.

Plug

What goes into an electrical outlet/receptacle.

Plumbing

Steel, Plastic, Copper are common pipe materials.

PSI

Pounds per square inch.  Measures water and air pressure.

Pneumatic tank

Pressurized tank in building basement to supply water to higher levels.  Causes air to be dissolved in water, and takes up floor space.

Point Grid

1 of 2 ways to calculate artificial light levels:

E = cos 0/d squared

• E=illumination at receiving surface
• 0 = intensity at the source when viewed from direction of receiving source
• d= distance from source to surface

Poly chlorinated biphenyls

Carcinogen in water supply

Power Factor (PF)

VxI=PF   (voltage x amps = power factor)
In an electrical circuit, the ratio of real power in watts to the product of voltage and current.

Power Level (PWL)

Logarithmic expression for the acoustical power at the source of a sound.  Also known as the Acoustical Power Level.

Power Grid

Type of floor (also CELLULAR METAL FLOORS) where power and cable services are contained = allows for flexibility in layouts.

Power Towers

Stationary towers with a collector of solar panels or a tank on top.  Used to generate electricity.

Power

P=VxIxPF

• P=power in watts
• V=voltage in volts
• I=current in amps
• PF=power factor in decimal form

Power factor is the cosine of the angle between the voltage wave and the resultant current wave. Ranges from 0.0 to 1.0 (%)

Preaction Sprinkler System

Type of dry pipe sprinkler system intended to compensate for the operational delay of a standard dry pipe system.  Sprinklers work with a sensitive fire-detection system, allowing water to fill pipes before sprinklers themselves are activated. Used where there is danger from serious water damage. Disadvantage: needs additional electrical and mechanical devices to allow water to fill pipes.

Prescriptive Code

Specifies how to build a building.

Pressure Regulators

Used when water pressure exceeds 80 psi…maintains pressure at 40-60 psi instead.

Pressure Release Valves

Safety devices to keep systems from exploding by opening when the pressure exceeds a pre-set maximum.  Required on water heaters.

Primary Winding

Winding that is used for input in a transformer.  SECONDARY WINDING is used for output.

Products of Combustion (POC)

Products of Combustion

Propane

When it leaks, it accumulates at bottom of a room.

Process of Heat Transfer

Flow of energy from area of high tem to area of low temp.  Thermal equilibrium occurs by the transfer of heat between areas of different temps.

RADIATION = slow rate                                                DARK, FLAT SURFACES = high absorptivity
EVAPORATION = latent heat                                        LIGHT, SHINY SURFACES = high reflectivity
CONDUCTION = 2 objects touch
CONVECTION = objects above/below

Profile angle

Angle of the shadow line – coincides with the altitude angle when the sun is perpendicular to the wall.  Varies by season.

PVC pipe

Used for water supply piping.

PPM

Parts per million.

Psychrometer

Wet bulb thermometer that swings to evaporate sleeve.

Psychrometric Chart

Graphic representation of the thermodynamics and properties of moist air.  Indicator of energy content of air and water vapor mixture.  Use to find dew points, to calculate enthalpy and to determine humidity ratios.  Used to calculate relationship of heat to airflow in AC design.  Shows Total Heat (latent+ sensible = enthalpy).  Shows Temp/Humidity/Relative Humidity/Enthalpy.

DB temp = vertical lines
WB temp = diagonal lines (lower left to upper right)
Rel Hum = curved lines
Amt of H2O in air – horizontal lines

PF  Power Factor

Use to calculate power for an AC circuit

Pneumatic Tank System

Water supply system that uses a pressurized tank, in basement, to supply upper floor water.  Alternative to downfeed system.

Radiant System

1 of 2 types of electrical heating systems:

• Radiant panels or wires embedded in ceiling – heat radiates.
• Baseboard heaters that heat air causing convection air circulation

Pros – only turn on in occupied rooms, only objects (not air) is heated.
Cons – wasteful, expensive, only use in very mild climates.

Radiation thru a Window (q r -or -SHGF)

A/k/a INSOLATION

Radiation

Transfer of heat by electromagnetic waves from warm surface to cool surface.  Net exchange of radiant energy between 2 bodies across an open space.  Depends on temp differential, surfaces’ thermal absorptivity, and the distance between energy source and receiver.
LIGHT = visible radiation
HEAT = infrared radiation

Reflected Glare

A/k/a VEILING REFLECTIONS
Prevented by diffuse light.

Receptacle

Commonly known as an outlet.  Place no more than 12 ft apart in residences.  All should be 3-pronged (3rd prong is grounded).  Do not place all receptacles in a room on the same circuit.

Recharge Rate

Water heaters are rated based on volume (capacity) and recharge rate (length of time to reheat itself once tank has emptied all hot water.)

Reflector

Reflection (lighting)

Light is bounced off material

Refraction (lighting)

Distortion of image thru a transparent material  - occurs to some extent in all transparent materials

Refraction (acoustics)

Sound can only be transmitted thru a medium, such as air or water, and can be refracted (bent) around objects.

Relay

Like a solenoid

Relative Humidity (RH)

% of water vapor in the air relative to the max amount of water the air can hold at a given temperature.
% of complete saturation at a given temperature vs. how much air could hold at that temp.
Air holds more water when warm than when cold.
RH changes with temperature.

Refrigeration Cycle

Basis of modern air conditioning.  Uses a special fluid (FREON) circulated in a closed loop.  Pressure in loop is varied using a pump and constricted section of tubing or valve, causing changes in temperature – and evaporation (which cools the water/air) or condensation (which heats the water/air).

Refrigeration systems

Architectural concerns – noise, vibration and heat.

Reheat

Adding sensible heat to air stream that was previously cooled.

Reverberation

Persistence of sound in an enclosed area after the sound source has stopped.  Considered live spaces. Function of surfaces’ absorptivity and space volume. R = x/k

Reverberation Time

The time it takes a 60 dB sound to completely die away in a closed room after the source has stopped.
Long R time causes unintelligible speech, but enhances music.

Resistance (R)

R=1/conductivity (1/K or 1/C) also x/conductivity – where x is material thickness
Reciprocal of conductance.  R increases as material thickness increases.  BIGGER R MEANS BETTER INSULATION.
Determines the temperature gradient and conduction of materials, is determined by conductivity.

Resistance (electrical)

One of 3 basic factors in electricity: potential (v), current amps), and resistance (ohms).  Refers to resistance to flow.
Series resistance – R total = R1 + R2 + R3 etc
Parallel resistance – 1/R total = 1/R1 + 1/R2 + 1/R3 etc

Resistivity (r ) (thermal)

Every material has it’s own resistivity, and conductivity.  In conductance, thermal resistivity is calculated by:  x/k=R
X is material thickness
K is material conductivity
R is RESISTANCE

Return Air

Previously processed air returned from rooms via ducts or a plenum.

Renewable Sources

Energy from the sun, wind, burning water, and moving water.  NOT STEAM, GAS OR NUCLEAR

Rigid Conduit

Safest conduit, with same wall thickness as Schedule 40 plumbing pipe.  Threaded fittings, galvanized in ext. apps – may be enamel for interior apps.  Can hold wires up to it’s rated capacity.

Rock Bed Storage

Active solar system that blows heated air from a collector to a large bin of course gravel, which store heat.  Air may be blown back in reverse at night to heat house.

Rods

1 of 2 parts of the eye’s retina – sensing devices that sense black and white images.

Romex Cable

An alternative to conduit in residential construction: ROMEX is sheathed wire (2 live, 1 ground) encased in plastic.  Officially called NM or NMC cable, strung inside walls and in exposed areas like garages.  Cannot be used in commercial garages, and cannot be embedded in concrete.  Some types are rated for underground burial.

Roof Pond

Use sliding insulation panels over a pond or bag of water on the roof.  During summer, pond is covered and absorbs heat from house.  At night, panels open and release heat to sky.  (Radiation is key process used.  Requires clear skies.)

Roof configuration for Photovoltaics

R Value

Resistance of an assembly
R=thickness/material conductivity

Rust

Oxidation of ferrous (iron based) fittings.

Sabin

Unit of sound absorption, named after physicist Wallace Sabine.  One unit = one sf of a totally absorptive surface (open window).

Sanitary Waste Systems

Remove contaminated water using gravity flow (not pressurized)

Saturation

Absorption of moisture.

Savonius

1 of 2 basic types of VAWT (vertical axis wind turbines):
DARRIEUS (eggbeater)
SAVONIUS (2 offset cups, like halves of a steel drum).  Not as efficient, but self-starting.  Generates electricity.

Sawtooth

Roof with a series of vertical or nearly vertical glass surfaces, usually facing north.

Schedule 40

Wall thickness of pipes is standardized by “schedules”, of which SCHEDULE 40 is the most common.

Secondary Winding

The winding in a transformer that  is used for power output.

Security Systems

Know different types of monitoring systems

Selective Surfaces

(Solar Collector Panels) – Surfaces which have high emissivity in one wavelength (solar) and low absorptivity in another (infrared).

Sensible Heat

Transferred heat energy that causes a change in DRY BULB temperature, but not a change in STATE.  Changes temperature, does not add moisture.

Septic Tanks

Lined chamber that collects sewerage. Liquid EFFLUENT seeps out to leaching fields or seepage pits to dissipate.
IN A HIGH WATER TABLE – use raised mounds with leaching beds

Series Resistances

One of 3 basic factors in electricity: potential (v), current amps), and resistance (ohms).  Refers to resistance to flow.
Series resistance – R total = R1 + R2 + R3 etc
Parallel resistance – 1/R total = 1/R1 + 1/R2 + 1/R3 etc

Service drop

All electrical services arriving on the site – includes wires from the main line, a transformer, a meter and a disconnect switch.

Sewerage Treatment Systems

Public System (waste treatment plant: settling chamber – sludge treatment – chlorinate water – reduce solid waste in an anaerobic digester (no oxygen present) to reduce volume by ingestion by bacteria.  Resultant sludge goes into a landfill, or used as fertilizer.

Private Systems:  Septic Tank w/leach field - Lined chamber that collects sewerage. Liquid EFFLUENT seeps out to leaching fields or seepage pits to dissipate.
Cesspools - Underground chamber w/porous bottom – allow seepage of waste to adjacent ground. Outlawed by most codes

Shading Coefficient (SC)

% of light transmitted compared to transmission of clear glass.

Shadow Mask

Representation of shading devices plotted onto a grid indicating sun path.

Sheathed Wire

An alternative to conduit in residential construction: ROMEX is sheathed wire (2 live, 1 ground) encased in plastic.  Officially called NM or NMC cable, strung inside walls and in exposed areas like garages.  Cannot be used in commercial garages, and cannot be embedded in concrete.     can it go underground?

Short Circuit

Occurs when 2 adjacent conductors lose so much insulation that current flows directly between them.  Creates very high (hot) current, can cause combustion.  Also means any situation where current is flowing where it shouldn’t be.

Siamese Connection

Required for all sprinkler systems - Y-shaped hose attachment at the base of a building, which allows the fire department to connect a pumper truck or fire hydrant to provide or augment water flow to a standpipe.  Duplex hose fitting.

Siamese Fitting

Fitting at lower end of a standpipe- arranged to accept either 2 or 4 hose connections from fire department pumpers.  A 2-1/2” connection must be provided at every floor level (above first fl) and at the roof and in all stairwells. 

Sidereal Time

Real or solar time.

Single Duct

Simplest forced air system…air sent out in constant volume…furnace runs till preset temperature is met.  Impossible to heat AND cool simultaneously.  Dampers on diffusers can control room temps.

Single Pipe

Single supply and return pipe, run in series or partly parallel.  Temperature decreases with eac successive register.  Low first cost, cannot have more than five registers.

Single-phase AC motor

1 of 4 types of general use motors:
Single-phase AC motors  - come in many sizes and shape, typ ¾ horsepower or less.
DC motor - used for small scale apps and elevators (continuous and smooth acceleration to high speed)
3-phase induction motors – larger motors, in constant rpm, reliable
Universal motor – either AC or DC, speed varies based on load (mixers, hand drills)

Single-phase (current)

Most basic form of power generation – single-phase alternator creates AC current.

Signal Equipment

Check MEEB

Site Drainage

Shading Coefficient (Sc)

Ratio of solar heat gained thru a window w/shading device to that of single pane double strength clear glass.
Similar to Transmissivity – relates light transmitted as compared to clear glass.

Shadow Mask

Representation of shading devices plotted onto Solar Plot.

Sling Psychrometer

Instrument that measures relative humidity or wet bulb temp.  Made of 2 thermometers, one with a wet sock on the bulb and one without.   The temp. differential is compared to determine relative humidity.

Soil

Sanitary drainage term referring to the waste from urinals, water closets, and fixtures if similar function.

Soil Stack

A large pipe that connects all the soil and waste lines throughout a building to a vent at the roof.

Soil lines

1 of 2 types of sanitary lines:

• Soil Lines carry water from toilets, urinals and similar fixtures.
• Waste Lines carry all other waste water from building.

Solar Cells

Directly generate electricity from sunlight.  Photovoltaics.  Flat thin cells of semiconductor made from silicon (sand).

Solar Design

Earth is tilted at 23.5 degrees.  Seasons are caused by the tilt of the earth, not distance from the sun.
Declination Angle = tilt of North Pole in relation to sun
Winter Solstice = -23.5 degrees
Summer Solstice – 23.5 degrees.
Equnioxes = 0 degrees

Altitude angle ALT= height of sun in the sky, measured straight up from ground
Azimuth angle AZ = compass orientation of the sun, measured east or west of due south
Shadow Line or Profile Angle = det. by interrelationship between AZ and ALT angles; or ALT only when sun directly faces wall

Summer sun on east façade, roof, horizontal skylights, and west.
Winter sun on south facing surfaces.

Hot/Temperate Climates:
Little glass on E & W walls – use vertical fins
Little horizontal glass/no horiz. skylights
Use clerestories or saw tooth roofs (face N in hot, S in cold)

Direct Gain Space…thermal mass in direct sunlight
Mass Wall…Trombe walls (convective loop), and water walls (lets light in, 5x more heat storage than concrete)
Indirect Gain…requires 4x as much thermal mass as a direct gain space for same effect.
Greenhouse…fans and exhaust fans
Super Insulated…R-20 walls and R-30 roofs
Double Envelope…self explanatory
Earth Sheltered…uses thermal mass of earth to regulate temps
Roof Pond…water bags on roof re-radiate energy as needed
Nighttime Flushing…dump hot air at night, seal building by day

DOMESTIC HOT WATER:
Flat Plate Collector…plate composed of tubes
Focusing Collector…parabolic trough with central tube
Open loop …fluid in system will be consumed
Closed Loop…fluid collects energy, does not mix with water in tank
Drain down/Drain Back Systems...empty collector fluids when temps drop
Batch System…a/k/a breadbox system
Thermosiphon System…storage tank is higher than collector, water circulates due to convection.

SPACE HEATING:
Air and Rock Bed Storage…warm air heats rocks, is recirculated at night
Desiccant System..sun bakes out moisture from air.
Absorption Refrigeration Cycle…uses lithium bromide to evaporate moisture out of a brine solution, then absorbs water vapor form clear water.
Steam Generation…solar collectors (inefficiently) can produce steam
Photovoltaics…solar cells.  Thin cells of silicon semiconductors create an electrical charge when exposed to light.  Equivalent to Direct Current batteries – can be converted to AC current using a synchronous inverter. 10-13% efficient.
Wind Turbines…need 10 mph or more, cost under $20K.
vertical axis (VAWT)  =  Savonius (slipped cups shape) or Darrieus (eggbeater shape)
horizontal axis (HAWT) = trailing vs. leading blade configurations (30 ft high)

Power Towers…stationary towers with collectors/tank on top.

Solar Envelope

Limits what can cast shadow on a site

Solar Heat Gain Factor

A/k/a SOLAR FACTOR
Formula for radiant gain = qr(= SHGF=SF) = Sg (SC) A

• Sg = intensity (Btuh/sf) on a surface area in a given orientation
• SC =the shading coefficient
• A = area exposed to direct sunlight

Solar Intensity (Is or Sg)

Sg – result of combined effects of ALT, AZ, orientation and time of day.

Solar Plot

Path of the sun plotted onto a grid.

Soldering

A/k/a SWEATING…FLUX applied to clean joints, pipe sections are heated, flux melts, joints assembled, solder melted onto joint.  When unit cools, pipe is completely sealed.  Process is reversible in copper.

Solenoid

Like a relay. May be used as an electromagnetic switch.
Rotating a wire loop between two magnetic poles creates a current.  Basic principle behind a GENERATOR. 
Wire wound spirally around an iron core to produce a magnetic field, used as an electric switch.

Solstice

Occur in winter and summer…when declination angle is –23.5 degrees (winter) and 23.5 degrees (summer)

Sound

Can only be transmitted thru a medium, such as air or water.  Velocity of sound depends on barometric pressure and altitude.  Sound can be reflected off surface, and be refracted (bent) around objects.

Sound Intensity Level (Is or Sg)

INTENSITY of sound is measured in WATTS per square centimeter, but INTENSITY LEVEL is in decibels!!!
IL=10 log (I/Io)
IL=intensity level
I=intensity of sound
Io=reference intensity value

Sound Power Level (PWL)

Power measurement at the source:  PWL=10 log W/Wo
PWL = sound power level
W=power at source (watts)
Wo=reference wattage (10 –12 watts)

Sound Pressure Level (SPL)

Pressure exerted by sound wave on a surface at any given location.

SPL= 20 log P/Po

SPL=Sound Pressure Level
P=pressure measured at the specific point (in newtons/meter2)
Po=reference pressure

Sound Transmission Class (STC)

Method of rating building components in terms of overall resistance to sound transmission.
Single-number rating for evaluation of a particular construction cross-section in terms of it’s transmission of airborne sound.  The higher the STC rating, the more effective the construction ia at stopping airborne sound.

Sone

Subjective system of measuring loudness, based on the reference point of: 1 sone = 40dB sound pressure level

Smoke Developed Rating

Numerical rating derived from a standardized fire test procedure.  Larger numbers indicate a greater density of smoke.

Smokeproof Enclosure

Continuous enclosed stairway separated from the building at each floor by an open vestibule that allows smoke to vent away w/o entering the stair.

Smoke Detectors

Fire alarm systems that contain photoelectric detectors that respond to smoke (pre-fire).  May be activated by dust, kitchen smoke.  Used in offices and apartments.

Sprinkler System

Extinguishes fires automatically by releasing water or other substances.

• Dry Pipe System
• Wet Pipe System
• Pre-Action System

Required in retail and areas of assembly over 12,000 sf. – All equipped with Siamese connections.   NEVER PAINT SPRINKLER HEADS.

NOTIFY INSURANCE COMPANIES OF CHANGES TO SYSTEM.

Specific Heat (Cp)

Ability of a material to store heat in relationship to the material’s weight.  Diff mtls can store diff amts of heat, even when they are at same temperature.  SPECIFIC HEAT is multiplied by a materials’ weight to determine thermal capacity.
Measured by # BTHs required to change material temperature by 1F.

Specular

Surface that maintains a reflected image (mirrors)

Sprinkler Systems

ALL REQUIRE SIAMESE CONNECTIONS OUTSIDE BUILDING SO FIREMAN CAN AUGMENT WATER FLOW.
Wet systems:  water in pipes, fusible links on heads, quick response, low cost
Dry systems:  no water in pipes, delayed response, use where freezing is an issue
Preaction Systems: A type of dry system that requires an independent fire-sensing device be triggered.  Not failsafe.
Deluge System: Fully open heads, water soaks entire space.

Key factors in layout design – NFPA standards?
Automatic sprinklers in occupancies where they are not required by code typically result in significant increases in allowable floor areas.

Squirrel Cage Blower

CENTRIFUGAL FAN – used to move large amounts of air.

Stack Effect

Hot, positive and outward pressure at top – cooler, negative and downward pressure at bottom (elevator shafts act like a smokestack).

Stack Vent

Length of pipe that rises above the highest branch drain (fixture) in a building.  Used to vent the soil stack.  Sole function is to vent to the outside air.

Static Head

Pressure generated at the bottom of a column of water that forces water up vertically.  Water is lifted 2.3 ft by 1 lb of pressure (psi) (.434 psi/ft)

Stages of a fire

Incipient (microscopic particles)     = Ionization detector
Smoldering (smoke)                         = photoelectric detector
Flame                                                = flame detector
Heat                                                  = heat detector

Standpipe

Vertical supply pipe for firefighting. – in all Group B Assembly places, and bldgs. 4 stories or higher.
Dry standpipes are empty (must be connected to fire hydrant via Siamese connection and a pumper truck)
Wet standpipes are pressurized and filled w/water – serve hoses attached to each floor.  All rooms within 30’ of a 100’ hose end. 1-1/2” hose connections.  Wet SP also has Siamese connections to allow water flow to be augmented from hydrants.
Combination standpipes – required in buildings over 150’ tall for stairways or smoke towers.  2-1/2” fire hose outlets, 1-1/2” hose racks.

Stagnation

Hot air rises, cool air falls – line of movement in between is still (caused by hot ceilings).

Star Connection

Method of connecting the windings of a 3-phase transformer in which one end of all 3 windings is connected to a common neutral center point forming a Y shape.  SAME AS A WYE CONNECTION.

Starter

Device which starts the arc in a neon or fluorescent lamp, or a contactor and overload relay used in starting some electrical motors.

Statue of Liberty Repair

Copper pitting from salt air, iron framework fatigue over time

Steam Trap

Valve which permits passage of water or air, but not steam.  Used with steam radiators.

Steel Pipe

BLACK IRON = Untreated steel, subject to rust and corrosion.
GALVANIZED STEEL = steel coated with a thin layer of zinc, comparatively rust resistant.
SCHEDULE 40 = most common wall thickness
Steel pipe is joined mechanically via threaded connections.

Step Up Transformer

Describes transformers that increase voltage.

Step Down Transformer

Describe transformers that decrease voltage.

Storm Drainage

Surface runoff from rainfall that is kept separate from sanitary waste; basically clean water.  Flows at high rates – would overwhelm sanitary sewer lines – water is typically not polluted.  Requires larger pipes than waste lines, gravity driven.

Structured Cabling

Wiring system that can support various communication applications like Local Area Networks and telephones.  Designed to accept frequent moves and changes.

Super Insulated

Consists of R-20 walls and R-30 roofs, taped seams on vapor barriers and foam-filed gaps at windows and doors.  Electrical wiring, switches and sockets are surface mounted to avoid wall penetrations.

Supply Air

Clean, temperature-adjusted air delivered to building zones for purposes of heating, cooling or ventilation.

Supply Ducts

Forced air systems distribute treated air thru building via supply ducts.  Supply air does not mix with return air.

Supply System (water)

Pipes, fittings and valves that supply potable water under pressure.

Surge Arrestors

A cushion or device within the water supply system that dampens the noisy effects of water flow.  A/k/a SHOCK ARRESTOR
Can be accomplished with a perpendicular air-filled section of vertical pipe.

Surface Water

Highly reflective of light at low angles of incidence.

Sun Charts

Sky map that shows sun’s path from rise to set at a given latitude on the 21st day of every month. 
Shows AZ, ALT and position above horizon. Use to design overhangs, shade devices, and calculate shadows.

• Months shown by Roman Numerals
• ALT by concentric circles
• AZ by radial lines

Sustainability

Focuses on pollution prevention, waste reduction, recycled content, local materials, natural materials, reduce construction waste.

STC

Sound Transmission Class.  Numerical rating of wall and floor systems for their efficiency in isolating sound transmission.  Higher rating = greater efficiency.

Swale

Shallow V-shaped sloping channels in the grass that funnel runoff to desired collection points.

Sweating

Method of soldering copper plumbing – or – the condensation of water on cold pipes or building materials.

System

Type of distribution method for distributing treated air or water.

Delta T

Temp differential between inside and outside, usually during winter, determined by subtracting the outside temp from the desired indoor temp.

Tank Type Toilets

A/k/a RESERVOIR TOILETS
Tank contains 3-5 gallons of water, which flush thru waste bowl to drain.

Different from FLUSH VALVE or FLUSHOMETER TOILETS that turn on water at a high rate of speed for a short time.

Tankless System

Water-heating system that services different demand levels.  Operates w/variable speed pumps that continually turn on or off to provide service.  System requires little space and no structural support.  Disadvantage: pumps have a short life.

Task Lighting

Lighting for a specific work surface or function.

Temperature

Measure of stored heat energy – NOT a measure of latent heat.
Temperature is never transferred, only heat energy is.

Temperature Gradient

Each layer of a structure has it’s own temperature (R layer/R total) Delta T total = Delta T layer

Total Heat

Sum of sensible plus latent heat stored in the air or a material.  Also known as Enthalpy.

Thermal Storage Capacity of Materials

Thermal Expansion

Pipes expand & contract due to temp changes, primarily affecting pipe length.
Change in L=Lk(T1-T2)
L=Length
k=coefficient of expansion
T1=original temperature
T2=final temperature

Thermal Relays

Protect motors against overload by shutting off the power when any part of the motor gets too hot.

Thermal Lag Factor

Numerical representations of the time that it takes radiant heat gain entering a space to be absorbed in the room air and become part of the load on the cooling system.  Lag time is determined by the thermal capacity of the materials within and surrounding the space.

Thermal Sailing

Set switches in anticipation of upcoming HVAC needs.

Thermosiphon System

Method of using a heated surface and resulting convection to move a fluid out of a space. 
In solar hot water heaters, the collector is below the storage tank, and the water circulates automatically by convection when it’s heated.
Can be used to ventilate a building by sending warm air out the top, and siphoning in cool air at the bottom.

Thermosiphoning

Use of convection to move air thru a building.  (Trombe Wall)

Three Pipe System

Independent hot and chilled water systems with a common return for both supply lines.

Three-phase induction motor

One of 4 general motors: These are larger motors that remain in constant RPM, power factors of 0.7 to 0.9, extremely reliable.

Three-phase

A version of alternating current in which there are 3 different circuits, each 120 degrees out of phase with the others, and 1 neutral or ground circuit.

P=VxIxPF

P=power in watts
V=voltage in volts
I=current in amps
PF=power factor in decimal form

Three-way Switches

When there are 2 or more doors in a room, and a light switch is placed at each door – each is called a 3-way switch.

Three-Wire Secondary

Single-phase transformer connection that consists of 2 sections. 
1 lead is at one end of the secondary.
2nd lead is at midpoint of secondary & is grounded.
3rd lead is connected to the other end of the secondary.

Use 1st & 3rd leads for 240 volt output.   Use 1st and midpoint leads for 120 volts.

Thrust Block

Carries load of water force where there is an elbow or change in direction (fire hydrant example)

Tile Drain Field

A/k/a LEACH FIELD  Grid of ceramic pipe laid underground – gaps between ends so liquid leaks out.

Ton

Amount of cooling required to create a ton of ice in a 24 hour period = to a steady rate of 12,000 Btuh.

Total Heat

Translucent

Characteristic of a material when light – but no image – can be transmitted.

Transformers

• Devices that change the voltage (not the power) in alternating current (AC). 
• Almost always step power DOWN to a building
• Can transmit power over long distances or make it usable for household purposes. 
• Can convert AC to DC
• Thermal rating = Volts x Amps
• KVA is standard (1000VA)  
• (Read MEEB)
• lines? voltages?

Transmissivity ( T )

Measure of how easily a material allows radiant energy to pass thru it (glass).  Glass is high transmissivity in visible light, but low in radiation.

Transmitted Light

Light that passes thru a material.  If an image is transmitted, material is TRANSPARENT.

Transmission (acoustics)

For every doubling of mass, TL increases by 5-6 dB.

Transmission Loss (TL)

Reduction of sound that occurs when a given wall transmits sound from one room to an adjacent room, expressed in decibels.

Trap

Keeps sewer gas from entering a building, U shaped pipe.

Trombe Wall

Form of mass wall that transfers heat by causing convective loop nto the room behind it, as well as conduction.

Two-pipe system

Hot or chilled water system having only a supply and a return line.  Cannot supply chilled and heated water simultaneously.

Two Wire Secondary

Single-phase transformer connection that has one wire grounded, which then becomes neutral.

Type I

Most fire-resistive Construction Type  (conventional wood structure is Type 5)

Type K, L or M

Designations for pipe wall thickness- K=thickest, L=most commonly used, M=thinnest

UBC

Uniform Building Code

Unitary Systems

HVAC system that pulls outside air into the serviced room thru a mechanical unit. Used w/large buildings in place of extensive ducting, and when separate utility bills are required.  Can be single zone, multi-zone, or heat pumps w/H & C functions.

Upfeed System

Water supply system that uses existing water pressure main to supply fixtures.  Building height limited to 40-60 feet.

U Value

Thermal conductivity of a given wall assembly.

U=1/sum of Rs

The thermal conductivity of a particular wall section expressed in BTUs per hour per Degree F per Square Foot

U=1/R

Smaller U means more insulation, less conductivity.
Smaller R means less insulation, more conductivity.

Vacuum Breaker

Automatic valve that admits air to a supply pipe rather than allowing pipe to suction or siphon polluted water back into the supply.

Variable Air Volume (VAV)

AC system that accommodates thermal load changes by varying the flow of supply air into a conditioned space instead of varying air temp.

Valves

Control the flow of water.  Allow selective shutdown of system.

• Angle Valves   (hose bib)

A/k/a SCREW & SEAT valve, or WASHER & SEAT valve.
Flow restrictor or metering valve, similar to a globe valve.

• Ball Drip Valves

Valve at lowest point of standpipe to ensure it stays dry

• Butterfly Valves

• Check Valves

Prevents water from moving backwards in a system (backflow preventer)

• Drain Valves

• Flushometer Valves

Valve that releases definite amt of water into a plumbing fixture each time it’s activated.

• Gate Valves

• Globe Valves

Turn water ON and OFF and METER or THROTTLE flow at intermediate rates.  Restrict flow even when wide open.

• Needle Valves

• Plug Valves

• Pressure Relief & Pressure Control Valves

Safety devices to keep systems from exploding by opening when the pressure exceeds a pre-set maximum.  Required on water heaters.

• Safety & Emergency Shut-Off Valves

Vapor Barrier

Always on the warm side of wall.  Where’s it go on water supply pipe insulation?

Viewed Angle

Angle of view depends on size of surface and your distance from it.  Affects heat transfer.

Veiling Reflections

A/k/a REFLECTED GLARE…prevented by diffuse light.

Vent Line

Pipes extending up from a fixture and thru the roof to allow airflow within a plumbing system.  Equalizes system water pressure too.

Vent Stack

4 “ vertical vent pipe that provides air circulation to and from all sanitary drainage lines – breaks the siphoning that would occur when water drops thru system - extends above roofline to open air.  Portion above last fixture is the STACK VENT.

Vertical Axis Wind Turbine (VAWT)

2 basic types of wind turbines:
Vertical Axis Wind Turbine (VAWT): 

• DARRIEUS (eggbeater)
• SAVONIUS (2 offset cups, like halves of a steel drum).  Not as efficient, but self-starting.  Generates electricity.

Horizontal Axis Wind Turbine (HAWT)
More common type in use today, available in leading (blades are upwind) or trailing (downwind) blade configurations

• Leading requires a tail like a weather vane, or a wind-sensing device.
• Trailing results in eccentric vibrations.

Vertical Transportation

Vestibule

A/k/a AIRLOCK

Vibration Isolator

Uses springs or neoprene pads beneath equipment to reduce vibrations.

Volt

Potential of electricity, akin to water pressure.

Voltage

V=IR
Know types used in a residence

Washer and Seat Valves

A/k/a ANGLE VALVES – or – SCREW AND SEAT VALVES – similar to Globe Valve too.
Can regulate or shut off flow.

Waste Lines

Do not carry raw sewerage, only used water.

Wastewater

A/k/a GREY WATER, does not contain raw sewerage.

Water

32F = freezing point    (180 BTUs required to evaporate a pound of water)
212F= boiling point     (1000 BTUs required to freeze a pound of water)

Gallon of water weighs 8.35 lbs.

Only material that expands when it gets cooler (just before freezing).

Water closet

Water Heaters

Water Temperatures

• Dishwashing/Laundry = 140 degrees F (hottest domestic application)
• Bathing/showering = less than 110 F
• Handwashing = 105 F

Water Usage

• 5 minute shower 7x week (2.5 gal/min) = 88 gallons
• Dishwasher 3x week = 35-55 gallons
• Washing machine 1x week = 40-55 gallons
• Water conserving toilet 2x daily = 50 gallons

Water Hammer

Thumping or rattling sound that occurs when a faucet is shut off suddenly,  Use surge arrestors to dampen the effect

Water Pressure

Water is usually supplied under pressure.  Water is lifted 2.3 ft by 1 lb of pressure (psi) (.434 psi/ft)

Water Table

Underground water level.

Water Supply Systems

Upfeed, Downfeed, Pneumatic Tank

Water Use

5 minute shower=12.5 gal
dishwasher=12-18 gal
washing machine=40-55 gal
toilet=3.5 gal/flush

Water Wall

A tank or collection of vertical tubes, filled with water and placed near window to collect heat energy from sunlight.  Stores 5x the heat per degree change per pound as concrete does.

Watt

Basic unit of electrical power. 

P=VxI                                                                                            1,000 watts = 1 kilowatt

• P= power in watts                                                  1,000,000 watts = 1 megawatt                       

• V= voltage

• I= the current in amps

Watt = Volts x Amperes in direct current systems 

Watt = 3.41 Btuh

Watts/cm2

Measurement of energy stored in a sound wave.

Wavelength

Lengths of one complete cycle or waveform, for light or sound waves. In light, the dominant wavelength determines color.

Wet Bulb Depression

Difference between dry bulb and wet bulb temperatures.

Wet Bulb

Thermometer wrapped in wet sock that evaporates when swung in air, allowing relative humidity to be taken into account.

Wet Bulb Temperature (WB)

Temperature attained by a glass thermometer whose bulb is covered with a wet sock and placed in an air stream moving at 1000 ft per minute.

Wet Standpipe System

Emergency fire fighting system connected to a constant, pressurized water system. Required for buildings of 4 or more stories. All pts. On floor must be within 30 feet of a 100-foot hose.  Siamese fittings for immediate use by firemen and occupants.  Fast acting and reliable, can’t be subject to freezing.

Wet Pipe Sprinkler

Sprinkler system that is constantly pressurized with water.  When a fusible sprinkler opens, water is immediately forced thru the sprinkler heads.

Wavelength

The wavelength of radiation is based on the temperature of the object.  Warm things are infrared, hot things are in visible spectrum

Wind Chill Index

Fictitious temperature assigned to a combination of actual temperature and wind velocity that has the same physiological effect as still air at the chill factor temperature.

Window Ventilation

Wind Pressure

Effects?

Wind Turbines

Windmills used to generate electricity from wind using a generator or alternator.  Requires wind speeds in excess of 10 mph.

Wiring

AMERICAN WIRE GAGE (AWG) standardizes sizes.
No sizes smaller than 14 gage should be used for building wiring.
Use of aluminum wire in small gages (#4 or less) is discontinued due to connection deterioration and metal fatigue.

White Noise

A/k/a MASKING NOISE – background sounds that enhance conversational privacy.

Wood types

Wye Connection

Method of connecting the windings of a 3-phase transformer in which one end of all 3 windings is connected to a common neutral center point forming a Y shape.  SAME AS A STAR CONNECTION.

Qv=Vx1.08x Temp Change

Heat loss thru infiltration

Xeriscaping

In dry climates, plant materials adapted to dry and desert climates.

Zeolite

Ion exchange process used in water softening.

Zeolite softeners

Replaces calcium carbonate with sodium carbonate by means of an ion exchanger (hard water “softener”)

Zonal Cavity Method

Calculation of the lumen output of lamps, the number of lamps in each luminaire, and the efficiency of the luminaire based on a Coefficient of Utilization (CU).  This method is most commonly used to determine the lighting requirements for offices, factories and commercial spaces.

Zonal cavity

A/K/A Room Cavity Method – or – Lumen Method   (not Point Grid Method)
Used when using a uniform distribution of a large # of fixtures. 
Considers direct lighting, ceiling reflectivity, wall mid level, zone between work surface and floor, and maintenance and dirt.
Based on CU (0-1 range, most fall between .5 and .8)

What goes into calcs?

Zones

Segments of building spaces grouped by cooling/heating needs and service.

Vent Stack vs. Stack Vent

Stack Vent is the portion of the vent above the last fixture
Vent Stack is the 4’ pipe that connects to all fixtures and runs thru the roof.

Decibel levels

What does increasing by x do to intensity?  (not linear)

Direct vs semi-direct vs. indirect lighting

STR vs. NRC?

Designation for plastic pipes?

What light is best if ceiling is black? Direct? Indirect?

WHAT’S A RESISTOR?

Gas in a doctor’s office?  CO/methane/O2  uses a ball valve

Identify elevator signal equipment at lobby

1 psi = 2.3’…how high can x psi push water?

What fixture has lowest glare?  Is cheapest?

What HVAC system is the most efficient?

Single phase vs 3 phase

TVL – double volts increases amps?

Most economical conduit for sub-slab chase?  PVC, Flex, Steel, IMC

Purpose of exterior disconnects?

Figure slope % between 2 pipes below grade given x and y dimensions

U=coefficient of heat transfer of a building section  ( #BTU/hr thru 1 sf when temp diff is 1 degree F)
K=coefficient of heat transfer of a material   (based on 1 inch thickness of mtl)
R=resistance to heat transfer of a bldg. section OR material    (R=1/U)