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What is a “criteria” air pollutant?
What is the difference between a primary and secondary National Ambient Air Quality Standard?
How is the location of an air monitoring station decided?
How large of an area does an air monitoring station represent?
What air quality factors should be considered when buying a house?
What do I do if I have a complaint about an odor or other air quality issues?
How can I get current air quality data?
How can I get historical air quality data?
Why can’t I burn my trash?
Who can I call about an indoor air quality problem?

• What is a “criteria” air pollutant?
  
  A “criteria” air pollutant is an air pollutant that has had a National Ambient Air Quality Standard (NAAQS) established for it by the U.S. EPA. There currently 7 criteria pollutants: sulfur dioxide, nitrogen dioxide, carbon monoxide, ozone, lead, particulate matter less than 10 microns in diameter (PM 10), and particulate matter less than 2.5 microns in diameter (PM 2.5).
  

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• What is the difference between a primary and secondary National Ambient Air Quality Standard?
   
  Primary standards are set to protect human health. Secondary standards are set to protect public welfare and take into consideration such factors as crop damage, architectural damage, damage to ecosystems, and visibility in scenic areas.
  

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• How is the location of an air monitoring station decided?
   
  Delaware has had air monitoring sites located around the state since the late 1960’s. The original focus of the monitoring network was on monitoring close to “point” sources (large facilities with high emissions). As air pollution control strategies were successfully implemented and the emissions from large facilities were brought into compliance with air quality regulations, the focus has shifted to pollutants that are more of a regional problem.
  
  Air monitoring stations are primarily used to house continuous instruments that measure “criteria” air pollutants (those that have established National Ambient Air Quality Standards). Monitoring for particulate matter is often accomplished by setting up instrumentation on sampling platform.
  
  Multiple factors are considered when deciding the location of air monitoring station. Sites are selected based on the pollutant or pollutants to be monitored, the population density, proximity to other monitoring stations (including those in other states) and operational efficiency. The U.S. EPA has developed siting requirements for each of the “criteria” air pollutants. These requirements include distance from trees, buildings and roadways, distance from major point sources, and probe height. Other factors include site security and access, availability of electricity and telephone service, aesthetics and local zoning issues, and long term (+10 years) site availability. Unfortunately the ideal monitoring site is virtually impossible to acquire, especially in urban areas.
  

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• How large of an area does an air monitoring station represent?
   
  Depending on the location of a station and the pollutant being monitored, the data from a given site can represent a large geographical area or a smaller local area impacted by specific sources.
  

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• What air quality factors should be considered when buying a house?
   
  Delaware’s overall air quality is good on most days of the year. The air quality problem that affects the most Delawareans is the build up of ground-level ozone on certain hot summer days. Ozone is a regional air quality problem that does not vary dramatically over distances of several miles.
  
  Probably the best advice is to become an informed consumer. Drive and walk around the area. Do you see any potential air pollution sources? Where are the major roadways? Does anyone in your family have any known allergies or personal health problems that could make them more sensitive to a specific pollutant? Ask the current residents and neighbors if they have observed any problems. Be aware that you can sometimes be bothered more by a small air pollution source that is close than by a large source that is farther away.
  

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• What do I do if I have a complaint about an odor or other air quality issues?
   
  Odors and other environmental complaints can be reported to the Environmental Emergency and Complaints 24-hour Hotline at 1-800-662-8802. After hours odor complaints are only investigated if 5 or more calls are received.
  

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• How can I get current air quality data?
   
  Near real time air quality data and other information is available on the Air Quality Management Section web page.
   www.dnrec.state.de.us/air/aqm_page/aqm_nets.htm  

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• How can I get historical air quality data?
   
  Historic air quality data is available on the world wide web at: www.epa.gov/airsweb  

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• Why can’t I burn my trash? 
  
  Burning of any type of trash is illegal throughout all of Delaware at all times of the year. The burning of trash emits large amounts of toxic air pollutants some of which may be cancer causing. The amount of air pollution from 35 average burn barrels has been estimated as the equivalent of 1 regulated hazardous waste incinerator. The burning of trash also emits pollutants that contribute to other air quality problems such as ground-level ozone formation, odor complaints, fine particles, and visibility.  

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• Who can I call about an indoor air quality problem?
   
  Indoor air quality problems are handled by the Environmental Health Evaluation Branch of the Division of Public Health. (302) 739-6619

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