T

TA

technical assistance

TAMS

toxic air monitoring system

TAPPI

Technical Association of the Pulp and Paper Industry

TC

target concentration

TCC

tag closed cup (method of measuring flashpoint)

TDF

tire-derived fuel

TE

Emissions tailpipe

TEVES

thermal enhanced vapor extraction system

TF

turbofan and turbojet engines

TFH

total fuel hydrocarbons

TGO

total gross output

TGCU

tail gas cleanup unit

TGV

toxic gas and vapor

THC

total hydrocarbons

THROX

thermal heat recovery oxidation unit

TIBL

thermal internal boundary layer

TIM

technical information manager

TP

turboprop engine

TPD

tons per day

TPH

tons per hour

TPH

total petroleum hydrocarbons

TPI

technical proposal instructions

TPY

tons per year

TRA

total residual ammonia

TRC

technical review committee

TRD

technical review document

TRI

Toxic Release Inventory

TRIP

Toxic Release Inventory Program

TRO

temporary restraining order

TRPH

total recoverable petroleum hydrocarbons

TRQ

threshold reporting quantity

TRS

total reduced sulfur

TRU

thermal processing or reclamation unit

TSD

technical support document

TSP

total suspended particulates

TSS

total suspended solids

TSS

turbine engines for aircraft designed to operate at supersonic flight speeds

TTN

Technology Transfer Network (EPA's program for dissemination of guidance documents and regulations)

TTO

total toxic organics

TUHC

total unburned hydrocarbons

TVH

total volatile hydrocarbons

TVP

true vapor pressure

TW

total weight

TWA

time weighted average

U

UAM

urban airshed model

UAO

unilateral administrative order

UAPSP

utility acid precipitation study program

UAQI

uniform air quality index

UARG

utility air regulatory group

UCC

ultra clean coal

UCL

upper control limit

UEL

upper explosive limit

UF

uncertainty factor

UFA

unsaturated flow apparatus

UFL

upper flammability limit

UL

Underwriter's Laboratories, Inc.

ULEV

ultra-low emission vehicle

U/M

upset and maintenance

UNEP

United Nations Environment Program

UPZ

upper perched zone

URL

upper reporting limit

USEPA

United States Environmental Protection Agency

USPHS

United States Public Health Service

UTL

upper tolerance limit

UV

ultraviolet

UWL

upper warning limit

V

vac

vacuum

VAC

volts alternating current

VALLEY

meteorological model to calculate concentrations on elevated terrain

VAP

vulnerability assessment program

vap d

vapor density

VCS

vapor collection system

VCU

Venturi Calibration Unit

VDC

volts direct current

VE

visual emissions

VEC

vehicle emissions certificate

VEO

visible emission observation

VERR

vehicle emissions repair report

VES

vapor extraction system

VHAP

volatile hazardous air pollutant

VHS

vertical and horizontal spread model

VHT

vehicle-hours of travel

VIR

vehicle inspection report

visc

viscosity

VISTTA

visibility impairment from sulfur transformation and transport in the atmosphere

VKT

vehicle kilometers traveled

VMT

vehicle miles traveled

VN

verbal notification

VOA

volatile organic analysis

VOC

volatile organic compounds

VOHAPs

volatile organic hazardous air pollutants

VOS

vehicle operating survey

VOST

volatile organic sampling train

VP

vapor pressure

VRF

vehicle repair form

VRO

variable resistance orifice

VRS

vapor recovery system

VSI

visual site inspection

VSS

volatile suspended solids

W

WB

wet bulb

WCED

World Commission on Environment and Development

WD

wind direction

WHO

World Health Organization

WICEM

World Industry Conference on Environmental Management

WL

warning letter

WLM

working level months

WMMA

Waste Materials Management Act

WMO

World Meteorological Organization

WMP

waste management plan

WRI

World Resources Institute

WS

wind speed

WSF

water soluble fraction

WTRF

Waste Tire Recycling Fund

WWF

World Wildlife Fund

X

XRF

X-ray fluorescence

Z

ZEV

zero-emission vehicle

ZID

zone of initial dilution

ZM

zone manager