Glossary

Engineered Systems, August, 2003

Here are some common abbreviations and terms found in the pages of Engineered Systems.

A

A/C--air conditioning

ach--air changes per hour

AE--architectural and engineering; or architect and engineer .

AFD--adjustable-frequency drive

AHU--air-handling unit

ASD--adjustable-speed drive

ASHRAE--American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.

ATC--automatic temperature control

B

BAS--building automation system

bhp--boiler horsepower; also, brake horsepower

BMS--building management system

C

CAD--computer-aided design

cfm--cubic feet per minute

CHW--chilled water

CMMS--computerized maintenance management system

C[O.sub.2]--carbon dioxide

COP--coefficient of performance

D

D-B--design-build

db--drybulb

DDC--direct digital controls

DOAS--dedicated outdoor air system

DOE--The U.S. Department of Energy

DX--direct expansion

E

EMS--energy management system

EPA--U.S. Environmental Protection Agency

F

fpm--feet per minute

G

gpm--gallons per minute

H

HEPA--high-efficiency particulate air

I

IAQ--indoor air quality

IS--information systems

L

LEED[R]--Leadership in Energy and Environmental Design, a designation by the U.S. Green Building Council

M

MEC--mechanical, electrical, communication

MEP--mechanical, electrical, plumbing

O

O&M--operations and maintenance

OEM--original equipment manufacturer

OA--outside air

P

PM--preventive maintenance

R

rh--relative humidity

RFP--request for proposal

RFS--request for submittal

ROI--return on investment

RO--reverse osmosis

RTD--resistance temperature detector

S

scfm--standard cubic feet per minute

T

TES--thermal energy storage

U

UV--ultraviolet

V

VAV--variable-air volume

VFD--variable-frequency drive

VSD--variable-speed drive

W

WAN--wide area network

wb--wetbulb

wc-water column