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State Implementation Plan for Air Quality: Glossary and Acronyms

A listing of useful terms and acronyms used frequently in the Texas State Implementation Plan (SIP) for air quality and the webpages related to it.


attainment demonstration: A plan that describes how a nonattainment area expects to meet the National Ambient Air Quality Standards (NAAQS) by the attainment deadline.

control strategy: Measures to deal with air pollution. Examples of control strategies include an emissions trading program or vehicle inspection and maintenance.

eight-hour ozone standard: The indicator of air quality acceptability as it pertains to ground-level ozone. The current threshold value for this standard is 0.070 ppm, measured as maximum daily eight-hour average concentrations. To attain the eight-hour ozone NAAQS, the three-year average of the annual fourth-highest daily maximum eight-hour ozone concentration must not exceed 0.075 ppm.

nonattainment area: A geographic area that fails to meet a NAAQS. An area must be officially designated by the EPA, under procedures set forth by the federal Clean Air Act, to be classified in nonattainment.

offsets (pollution offsets, industrial growth offset): The reduction of current emissions at a rate equal to or greater than the amount of emissions expected to be produced in a new project. The offset ratio is determined by the ozone air quality classification in a particular area.

one-hour ozone standard: The former indicator of air quality acceptability as it pertains to ground-level ozone. This indicator involves taking an average one-hour concentration of pollutants. An area meets the one-hour ozone NAAQS if the monitored ozone level does not exceed the standard of 0.12 ppm more than three times over a consecutive three-year period.

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ACT: Alternative Control Techniques

AFV: alternative-fuel vehicle

APA: Administrative Procedure Act

ASC: area source categories

ASM: acceleration simulation mode

BACM: best available control measures

BACT: best available control technology

BPA: Beaumont-Port Arthur

CAMx: Comprehensive Air Model with Extensions

CARB: California Air Resources Board

CFR: Code of Federal Regulations

CMSA: Consolidated Metropolitan Statistical Area

CNG: compressed natural gas

CO: carbon monoxide

COAST: Coastal Oxidant Assessment for Southeast Texas

CTG: Control Technique Guidelines

DERC: discrete emission reduction credit

DFW: Dallas-Fort Worth

DPS: Texas Department of Public Safety

DV: design value

EGF: electric generating facility

EGR: exhaust gas recirculation

EI: emissions inventory

ELP: El Paso

EPA: United States Environmental Protection Agency

EPN: emission point number

ERC: emission reduction credit

FACA: Federal Advisory Committee Act

FCAA: federal Clean Air Act

FIP: federal implementation plan

FMVCP: Federal Motor Vehicle Control Program

FR: Federal Register

FTE: full-time equivalent employee

FTP: File Transfer Protocol

g/hp-hr: grams per horsepower-hour

GIS: geographic information system

g/mi: grams per mile

GVWR: gross vehicle weight rating

HAP: hazardous air pollutant

HB: House Bill

HC: hydrocarbon

HDD: heavy-duty diesel

HDDV: heavy-duty diesel vehicle

HDV: heavy-duty vehicle

HGB: Houston-Galveston-Brazoria

HOV: high-occupancy vehicle

hp: horsepower

HPMS: Highway Performance Monitoring System

kg/ha: kilograms per hectare

km: kilometer

LDT: light-duty truck

LED: low emission diesel

LEV: low emission vehicle

LNG: liquefied natural gas

LSG: low sulfur gasoline

m: meter

MACT: maximum achievable control technology

MMBtu: million British thermal units

MPA: metropolitan planning area

mph: miles per hour

MY: model year

NAAQS: National Ambient Air Quality Standards

NNSR: nonattainment new source review

NOx: nitrogen oxides

NOy: nitrogen species

NSR: new source review

NWS: National Weather Service

O3: ozone

OAQPS: the EPA's Office of Air Quality Planning and Standards

OBD: on-board diagnostics

OSAT: Ozone Source Apportionment Technology

OTAQ: the EPA's Office of Transportation and Air Quality

PAMs: photochemical assessment monitoring sites

Pb: lead

PEI: periodic emissions inventory

PM: particulate matter

PM2.5: particulate matter smaller than 2.5 microns

PM10: particulate matter smaller than 10 microns

ppb: parts per billion

ppm: parts per million

ppmv: parts per million by volume

psi: pounds per square inch

psia: pounds per square inch absolute

QA/QC: quality assurance / quality control

RACT: reasonably available control technology

REMI: Regional Economic Modeling, Inc.

ROP: rate of progress

rpm: revolutions per minute

RVP: Reid vapor pressure

SAE: Society of Automotive Engineers

SB: Senate Bill

SCC: source classification code

SIC: Standard Industrial Classification

SIP: state implementation plan

SO2: sulfur dioxide

SOx: sulfur compounds

SOCMI: Synthetic Organic Chemical Manufacturing Industry

SULEV: super ultra low emission vehicle

TAC: Texas Administrative Code

TCAA: Texas Clean Air Act

TCEQ: Texas Commission on Environmental Quality

TCM: transportation control measure

TERP: Texas Emissions Reduction Plan

TIP: transportation implementation plan

TMCP: Texas Motorist's Choice Program

TNRCC: Texas Natural Resource Conservation Commission (the former name for the TCEQ)

tpd: tons per day

tpy: tons per year

TSP: total suspended particulate

TTI: Texas Transportation Institute

TxDOT: Texas Department of Transportation

VID: Vehicle Identification Database

VIN: vehicle identification number

VIR: Vehicle Inspection Report

VMAS: Vehicle Mass Analysis System

VMEP: Voluntary Mobile Source Emissions Reduction Program

VMT: vehicle miles traveled

VOC: volatile organic compounds

VRF: Vehicle Repair Form

WOE: weight of evidence

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