Abstract: On July 6, 1998, employees of Chemical Formulators, Inc., a facility which is a bleach manufacturing plant involved in drumming chlorine in one-ton cylinders and 150-lbs cylinders, were in the process of starting up the cylinder filling station. One of the employees, after hearing a thumbing noise, turned off the pump circulating bleach through the production tank scrubber and 15 lbs of chlorine were released. Sixty two employees of Trident Shipworks, Inc., a neighboring business, were transferred to a hospital and fifty five were released. Employees #1-7 were hospitalized for chemical inhalation. Several factors contributed to the incident. The vacuum line valve was left open, the alarm to the vacuum lines was off, and the circulating pump through the scrubbing system was off.