Along with warmer weather comes ozone season in Delaware, and the U.S. Environmental Protection Agency (EPA) and its partner agencies host an Air Quality Awareness Week during the first week of May.
Interest in air quality has been increasing since at least the turn of the 20th century. If you’ve ever watched Netflix’s “The Crown,” episode four centers on England’s London Smog event of 1952 which was a deadly example that kicked off the creation of laws to improve air quality. In the U.S., as noted in the show, the 1948 toxic smog event in Donora, Pennsylvania also turned lethal.
The Donora smog event resulted in 20 deaths and thousands of respiratory complications. Growing air quality concerns led to several federal and state programs to understand air pollution through monitoring.
As a result, air pollution monitoring in Delaware began in the 1950s. In 1970, the same year the EPA was established, Governor Russell Peterson created the Delaware Department of Natural Resources and Environmental Control which consolidated previous monitoring efforts under its umbrella.
Ozone in the 21st Century
It goes without saying why our air quality is important, but what role does ozone play in the equation? Ozone is a colorless, naturally-occurring gas found in two layers of the atmosphere. In the upper layers, ozone protects life on Earth by absorbing some of the sun’s ultraviolet rays.
Air Quality Monitoring StationBut in the layer closest to the ground, ozone is an air pollutant that is a key ingredient of smog and damages lung tissue, aggravates respiratory conditions and makes people more susceptible to respiratory infections. Children are especially vulnerable to ozone’s harmful effects.
For this reason – and to monitor other pollutants in the air we breathe – DNREC maintains an air monitoring network, made up of 11 permanent sites throughout the state.
The monitoring stations are climate-controlled trailers or shelters that house and protect the analytical instruments which staff from the DNREC Division of Air Quality maintain and operate. Computers allow for continuous monitoring 24/7, and help improve both the quantity and quality of data. The network is evaluated annually to address changing monitoring rules, improvements in technology and trends in air quality.
Measuring More Than Ozone
Monthly CheckIn addition to monitoring ozone levels, the stations measure other pollutants identified by the EPA. The EPA has standards for six major pollutants including carbon monoxide, sulfur dioxide, nitrogen dioxide, small and large particulate matter, and lead.
Delaware monitors for these and other pollutants and releases an annual report tracking changes.
New Castle County has the most monitoring stations – seven. That’s mainly because it has the largest population and number of pollution sources.
Read more: Breathing Easier – Delaware’s Air Quality Monitoring Network