New Study Will Help Pool Operators Understand How to Best Improve Indoor Air Quality at Public Pools

SOURCE: Council for the Model Aquatic Health Code

More and more swimmers are flocking to indoor pools and waterparks for physical activity and fun, especially during the cold months of winter and early spring. As the use of indoor pools, water parks, and other indoor facilities with aquatic attractions continues to rise, so does the chance that disinfection byproducts (DBPs) will form in the water. DBPs can be harmful and cause illness in swimmers and spectators. Researchers are launching a new study to understand the best ways to prevent the build-up of DBPs in these venues.

DBPs are formed when the chlorine used in pools to kill germs binds to the body waste swimmers bring into the pools (for example, sweat and urine). When DBPs build up in the water, they can escape into the air over the pool. DBPs that build up in the air can accumulate near the water’s surface, where swimmers and spectators can breathe them in. Whether or not this happens may depend in part on the characteristics of the facility’s air handling system. Between 2000 and 2014, the Centers for Disease Control and Prevention reported 22 outbreaks and more than 1000 cases of illness linked to DBPs, excess chlorine, or altered pool chemistry at public aquatic facilities.

The Council for the Model Aquatic Health Code, through its Indoor Aquatic Facility Ventilation Design and Air Quality Ad Hoc Committee, is partnering with Purdue University and Michigan State University to conduct a study that will determine the exact operating conditions for indoor pools that will help prevent the buildup of DBPs in the air and lead to air quality measurements known to be safe for swimmers and patrons. The study will also help identify real world design and operational issues impacting air quality and climate control for indoor aquatic facilities. The results of the study will be used to update design and operational guidelines in the Model Aquatic Health Code, with the goal of improving the health and safety of all swimmers and spectators who visit indoor pools. 

The first phase of the study is already underway. Researchers are measuring water and air quality at indoor pools in Michigan and Indiana before and during competitive swim events that involve large numbers of swimmers.

The second phase of the study will involve research at approximately 15 additional facilities. Researchers are collecting basic information from indoor aquatic facility operators on air handling systems and issues through a brief survey at www.cmahc.org/air-quality-survey.php.  The survey results will be used to select the 15 additional pools for phase 2 of the study. Participating facilities will remain anonymous.