### GLOSSARY OF TERMS AND ACRONYM S

AQI Air Quality I ndex, dail y forecast to the public about ai r qualit y on a 24-hour basis. Air Quality Monitor Device measuring ozone and PM levels at various locations throughout th e Washington r e gion. APU Auxiliary Power Units, an electrical device that provides a low-emission alternative to constant idlin g for large diesel engines. ASIP Association for Southeaste r n Integrated Planning. Attain m e nt A designation given to an area that does meet the fede ral health-bas ed air quality standard for a pollutant

. Attain m e nt (1-hour ozo n e) The expected num bers of day s per calendar y ear with maximu m ho url y average concentrations above 0.12 ppm is equal to or less than 1. Attain m e nt (8-hour ozo n e) The 3- y ear average of th e annual fo urth- h ighest dail y maximu m 8-hour average ozone concentration is less than or equal to 0.08 ppm

. Attain m e nt (Annual PM 2. 5 ) The 3- y ear average of the annual m eans i s less than or equal to 15.0 μ g/ m 3 . This

co mp arison shall be based on 3 consecutive, comp let e y ears of air quality data. Attain m e nt (24-hour PM 2. 5 ) The 3- y ear average of the 98th percentile values at each m onitoring site is less than or equal to 65 μ g/m 3 . This comp ari s on shall be based on 3 consecutive,

co mp lete y ears of air quality data. AQPAC Air Quality P ublic Advisory Committee. BACT Best available control technolog y. Bu mp -up/Reclassifi cation Process by w h ich areas fai ling to attain the air quality standard by the assigned date are redesignated to a m o re stringent nonattainm e nt category. CAAA Clean Air Ac t A m end m ent s of 1990. Classifi cation Federal desig n ation indicating the severity of a region' s air quality problem . A region' s classification determines the da te on which a region mu st attain the CAAA r e quire m e nts. Clean Air Partners Non-profit re gionall y

- spo n s ored organization in th e Baltim o re-Washingto n m e tro area that educ ates business es and the pub lic to take actions to reduc e ozone, especially on Air Quality C ode Red Action Day s

. CLRP Constrained Long Range Plan; lists expected changes to transportation infrastructure over the next 20 y ears. Control Measures Pollution control m e asure i mpl e m ented as part of a re gional air qua lity plan. Contingenc y Measure s Pollution control m e asure s to be imple m ented after the fact if the re gion fails to de m onstrate r a te of progress toward or attainment of an air quality s t andard. CTG Control Technique Guidance, co m e s in the form of docu m ents fro m EPA. DCDOE District of Colum b ia Departm e nt of the Environm ent. Design Value The U.S. EPA’ s official defin ition: “a design value is the mathematically determ ined pollutant conc entration at a particular site that mu st be reduced to, or maintained ator below the National A m bient Air Quality Standard to assu m e attain m e nt.” The design v a lue num ber tells us how a particular site or area

co mp ares wit h the National Am bient Air Quality S t andards (NAAQS). Design Value (1-hour Ozone) The 1-hour o z one design v a lue is the fourth hi ghest 1

- hour m a ximum ozone concentration at a m onitoring site durin g a continuo us three y ear period. Values of 125 ppb and above are exceeding the 1-hour ozone health standard. Design Value (8-hour Ozone) The 8-hour o z one design v a lue is the fourth hi ghest 8

- hour m a ximum ozone concentration at a m onitoring site averaged over a con tinuous th ree y ear period

. Values of 85 ppb andabov e are exceedi ng the 8- hour ozone health standard. EPA U.S. Environmental Protection Agenc y

. E m ission Inventor y A document that details the am ounts of projected em issions from ar ea sources

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over tim e. In cludes four types of e m issi on sources: stationary point sources, are a sources, nonroad sources, and on-road m obile sources. Exceedance Condition created when an air quality monitor registe r s ozone or PM levels exceeding the federal healt h standard. FHWA Federal Highway Adm i nistration. General Conf orm ity Federally -required process during which Federal projects are evalua ted to ensure that the y are consistent with the region' s air qualit y pl ans. IAD Dulles International Airport, site of a weather m onitor. IAQC Interstate Air Quality Council; a counc il, consisting of the chief environm ental appointees of the Chief Executives and the chief transportation appointees of the Chief Executives. I/M Inspection and Maintenance programs that require vehicle owners to have their vehicles ' e m i ssion sy stem s regularly tested and repaired, if necessa ry

. Lead Monitor The m onitor in the regi on with the highest De sign Value. L D T L i g h t

- d u t y tru c k s

. LTOs Landing and Take-Off cy cles for aircraf t

. MACTEC An engineering and co nsul ting firm und er contract to OTC. MDE Mary land De partm e nt of the Enviro nment. Mid-Course Review The Mid-Course Revie w is inte nded to show the progress being m a de to improve air qualit y in a nonattainment area and the efforts underway to assure that all

necess ary steps are taken to reach the fede ral health standard for the relevant standard b y th e attain m e nt date. MDPC Metropolitan Develop m entPolic y Committee; a COG co mm itt ee of planni ng directors. M S A / C M S A M e tr o p o l i t a n Statistical Area/Consolidat ed Metropolit an Statistical Area; serve as the presump ti ve boundary f o r nonattainm e nt areas. MOBILE6 EPA m odel used to esti m at e levels of mobile em i ssio n s. Mobile Budg et Cap on m obile em issions set in the SIP and used in tr ansportation conform ity

. MWAQC Metropolitan Washington Air Quality C o mmittee. MWAQC TA C Technical Ad visory Committee, advices MWAQC on technical issu es. MARAMA Mid-Atlantic Regional Air Ma nagem e nt Association; an RPO. MWAA Metropolitan Washington Airports Authorit y

. N A A N o n

- A t t a i n m e n t A r e a

. NAA QS National A mbient Air Quality Standard . A m bient sta ndards for six pollutants includin g ozo n e, carbon monoxi de, nitr ogen di oxide, lead, particulate m a tter, and oxides of sulfur specificall y regulated under the U.S. Clean Air Ac t of 1990. Areas designated as nonattain m e nt mu st adopt State I mplementation Plans to reduce em issions in or der t o comp ly with the standard by th e attainment date. NEI National Em issions Invent ory

. The Na t i onal Em issions Inventory i s the m o st

co mp rehensi v e esti m at e of criteria pollutantem i ssio n s in the United States. The inventory represents a maj o r effort by the individual states to quantify their local and regional contributi ons to air qualit y

. Data fro m the NEI are used for air dispersion modeling, regi o n al strategy d e velopment, regulation setting, and tracking trends in em issions over time. NESCAUM Northeast Sta t es for Coordinated Air Use Manage m e nt

. Nonattain m e nt A designation given to an area th at does not m eet the f e deral health- b ased air qualit y standard for a poll u t a nt. NOx Nitrogen oxi d e , a precursor to ozone for m ation. Organic Carb on Carbon em ission, a precursor to PM f o rmation. OTC Ozone Trans port Comm i s sion, a commission of air directors fro m northeastern

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and m i d-Atlantic states affected by trans ported ozone polluti on; an RPO. Ozone A pollutant ( O 3 ) form ed from chemical reactions in the atm o sphere involvi ng precursors (N Ox and VOC) in the presence of sunlight and heat. PEI Periodic Em issions Invent ory

. The Cle a n Air Act [ under Section 182(a)(3)(A)] requires that state and loca l agencies de ve lop a perio d ic em ission inventory (PE I) for ozone nonattain m e nt ar eas cl assifi ed as marginal and above. T h e PEI is a tool used to m onitor a nonattainment area’ s progress in attaining the National Am bient Air Quality S t andards (NAAQS) for ozone. A PEI for an ozone nonattain m e nt area is required to contain em issions of ozone precursor poll u tants (specifically VOC and NO x) from Point Sources, Are aSources, On-road Mobile Sources, Non-road Mobile Sources, and Biogenic S ources. A PEI is to be comp iled every three y ears until attainm e n t of the National Am bient Air Quality S t andards (NAAQS) for ozone is reached. PJM Distribution grid for electricity that incl udes Pennsyl vania, New Jersey and Mary land. PM 2. 5 Particulate matter, fine particulate. Particles of less th an 2.5 m i crons in diameter are refe rred to as fine particulate. RACM Reasonably available control m e asure. RACT Reasonably available control technolo g y

. REC Renewable E n ergy Certificate. Retrofit Installation of polluti on control devices on existing equipm ent, suc h as particulate filters and cat aly tic converters. RFP Reasonable Further Progre ss. ROP Rate of Progress. RPO Regional Planning Organization in CAAA, such as OTC, NESC AUM. RPS Renewable Energ y Portfo li o Standard A c t of 200 4, a District of Colum b ia law. RSD Re m o te s e nsi ng device, us ed in the field to detect m o t o r vehicles with em i ssions exceeding allowable li m its

. SI Spark-Ignition engines, such as gaso line m arine engi nes, including out board, personal watercraft and jet boat. SIP State I mple m entation Plan, the air quality plan. 1-hour S t andard Ozone standard setting the ma ximu m average ozone concentration over a onehour perio d

. 8-hour S t andard Ozone standard setting the maxi mu m average ozone concentration over an eighthour perio d

. 24-ho ur Stan dard PM standard setting the maximu m average concentration o v er a 24 -hour perio d

. Annual Standard PM standard setting the maximu m average concentration over a one-y ear period. Sulfates/SO 2 Sulfur di oxid e , a precursor to ozone andPM form atio n. TAC Technical Ad visory Committee of the MWAQC. TCM Transportation Control Me asure. TDM Transportation Dem a nd Model; a TPB m ode l used t o esti m ate tr a v el demand in the Washingt on regio n

. TERM Transportation Em is sion Reduction Measure. TPB National Capital Region Transportation Planning Boar d, bo d y resp onsible for developm ent of regional tr ansportation plan. tpd tons per da y

. tp y t o n s p e r y e a r

. TIP Transportation Improvement Plan; a sho r t term transp ortation plan produced b y TPB, usuall y covering a fiv e -y ear period. Transportation Conform ity Federally -required process during which the regional transportation planning

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board ensures that expected transporta tion em i ssions are consistent with the region' s air qualit y plans. VADE Q Virginia Depart m e nt of Environm ental Quality

. VISTAS Visibility Improvem e nt St ate and Tribal Association of the Southeast; an RPO. VMT Vehicle Mile s Traveled. VOC Volatile organic compound, a precursor to ozone for m ation. Voluntary Measure Pollution control m e asure s that are not regulatory in nature. WOE Weight of Ev idence.

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