One commonly forgotten component of good indoor air quality is radon gas. Radon gas is an odorless, colorless soil gas that is a by-product of the breakdown of uranium in soil, rock, and water that gets into buildings and schools and into the air we breathe. Only the visible components of the air quality are evaluated and included in most indoor air quality programs, which means that radon can often go overlooked.
Yet, high levels of radon gas may have significant health effects. Elevated radon levels can occur in any indoor environment, and exposure in the school or workplace can increase the risk of developing lung cancer.
Background levels of radon gas in the ambient outdoor air are typically below one picocurie per liter of air (pCi/L). A “picocurie” is the unit of measurement for radon gas concentrations used by the United States Environmental Protection Agency (EPA). The level of concern as established by the EPA is 4.0 pCu/L.
Locations where people spend much of their time, such as homes, offices and schools, may be a source of radon exposure.
The initial concern about radon gas was in single family residences and schools. The protocols subsequently developed included one or two samples in a house and samples in each classroom of a school. Elevated radon gas levels are primarily a concern in spaces closest to the building’s foundation, such as basements and ground floor spaces. However, office buildings and multi-unit apartments are more complicated structures with a different set of air flow dynamics and pathways for radon entry.
Radon Testing In Buildings
Commercial buildings and multi-family housing, especially those with lower level-parking garages, utility and storage rooms, plumbing and other utility chases and heating, ventilating and air-conditioning systems, require a different approach to testing.
Current protocols for testing were developed by the American National Standard Institute (ANSI) and American Association of Radon Scientists and Technologists (AARST). These protocols currently recommend testing all basement spaces, such as utility and storage rooms, occupied spaces above a garage, 10% of spaces in the floor above and staggered spaces in additional above spaces so the tested units on one floor are not directly above tested units directly below.
In commercial or office spaces, there is a concern for worker safety since every employer has a legal obligation to provide and maintain a safe and healthful workplace for employees, according to the California Occupational Safety and Health Act of 1973.
Residential care facilities, public housing, governmental offices as well as schools must have testing conducted by a certified individual. In California, the certifying entity is the California Department of Public Health which requires performance testing and continuing education for certification.
Testing is the only way to determine the concentrations of radon gas in a classroom or office.