The Technical Services Branch conducts the following major activities and functions:

• Daily sample collection for concentrations of particulate matter less than 2.5 microns in diameter (PM-2.5).
• Continuous monitoring of carbon monoxide, nitrogen dioxide, sulfur dioxide and ozone concentrations at several key locations throughout the District of Columbia.
• One-in-six day sample collection for concentrations of PM-10 and particulate lead.
• Operates a Photochemical Assessment Monitoring station (PAMS) during the ozone season (May to Sept.).
• Conducts overt and covert auditing of the Enhanced Vehicle Emissions Inspection/ Maintenance
• Program. Performs special monitoring studies.

Section 110(a)(2)(C) of the Clean Air Act requires ambient air quality monitoring as a component of the District's State Implementation Plan (SIP) for the purpose of determining attainment status relative to the National Ambient Air Quality Standards (NAAQS) and to track national and local air quality trends. Uniform criteria for measuring and reporting air quality, quality control/quality assurance procedures and provisions for reporting of a daily air quality index are required by Section 319 of the Act. To satisfy these requirements, EPA established Part 58 of Title 40 of the Code of Federal Regulations (40 CFR Part 58) which provide detailed requirements for air quality surveillance and data reporting for all the pollutants for which air quality standards have been established (i.e. ozone, sulfur dioxide, carbon monoxide, nitrogen dioxide, particulate lead and particulate matter less than ten microns in diameter, or PM-10).

Pursuant to these requirements, the Technical Services Branch of the District's Air Quality Division operates and maintains an extensive ambient air quality monitoring network within the District. The locations of the monitoring stations were selected either because they represent locations of high population density and therefore the air is representative of what a large population is exposed to, or because they represent locations where, as a result of air pollution source strengths, source population and meteorology, high concentrations of particular pollutants are expected.

Data generated from this monitoring network is carefully reviewed, edited and subjected to rigorous statistical quality assurance analysis prior to submittal into the national air quality database. This submittal is made via computer to the Aerometric Information Retrieval System-Air Quality Subsystem (AIRS-AQS) on a monthly basis for the gaseous pollutants and on a quarterly basis for lead and PM-10. A comprehensive systems audit and network review is performed annually by EPA regional staff during which all aspects of the monitoring program (e.g. station location, monitoring methodology, record keeping, calibration procedures and frequency, individual monitor performance, etc.) are examined for adherence to the appropriate regulatory requirements.

District of Columbia Vehicle Emission Inspection Program (I/M)

The Federal Clean Air Act spells out air quality standards that all areas of the United States must meet. Motor vehicles are one of the major causes of air pollutants in metropolitan areas. Vehicle exhaust emissions include carbon monoxide, hydrocarbons, and oxides of nitrogen. Vehicle emission testing assures that in-use vehicles are within specified standards.

The District of Columbia is one of over 90 metropolitan areas in 5 states with air pollution levels higher than federal health standards. Approximately one-third of the volatile organic compounds (mostly hydrocarbons) and 60% of carbon monoxide present in this area are created by motor vehicles.

Purpose:

• vehicles that exceed exhaust and evaporative emissions prevent registration until vehicles meet emission standards Facts: Vehicle emissions pollute our air and help create ground-level ozone, a major component of smog. The pollution ends up in our lungs, on the ground, on crops, and in our water supply.
• Intense sunlight "cooks" pollutants, causing summertime Ozone Action Days when children, the elderly and people with breathing problems are warned to stay inside.
• Rain and snow carry air pollutants into surrounding rivers and streams.
• Working in partnerships with states throughout region, the District's Vehicle Emissions Inspection Program will significantly improve the quality of the air we breathe and the waters in which we work and play.
• I/M is a big part of the solution. By manufacturing, cleaner cars and cleaner burning, fuel, installing vapor recovery nozzles at gas stations, and implementing more efficient controls on utilities and industry, government and businesses are working, together to make The District's air and water cleaner and healthier.
• Nationally, the recent air quality levels are the best on record. The air quality improvement is happening while the U.S. population increased 29%, the gross domestic product increased 104% and vehicle miles traveled increased 121 %. However, despite the progress, air pollution remains a major public health issue. The District's populace still lives in areas that do not meet minimal air quality standards.
• We need vehicle inspection and maintenance program in the District of Columbia to help us identify the cars that do have emissions problems. We accomplish our task by identifying vehicles that are the gross polluters, and require repairs that ultimately reduce the harmful pollutants that come from the vehicle tailpipes.
• We will continue to perform QA/QC data collection, instrument calibrations, review training certification for emission inspectors, provide station performance review, and all required EPA reporting.