Abstract: On August 3, 1998, six people were exposed to airborne chlorine vapor at the Airways Pool. Employee #1 and Employee #2 were employed by the City Parks Services as lifeguards or swim instructors. The other four were patrons of the public swimming pool operated by the City of Fresno Parks and Recreation Division. The local hazardous materials team responded and turned off the chlorine vapor leak at its source. The chlorine problem occurred when one of the valves that carried chlorinated water back to the pool was not opened completely, thereby allowing a concentration of highly chlorinated water to build up at the valve. The employees had been instructed in the proper method of shutting down the valves in order to clean the filter baskets, but then to ensure that the valves are opened completely to allow proper circulation. All exposed parties were sent to local emergency rooms and were treated and released with no lingering health problems.