Wastewater Treatment Operator Certification Practice Test

What is the permissible exposure limit for chlorine gas vapor during a normal 8 hour workday and a 40 hour work week?

1. 0.1 ppm

2. 0.5 ppm

3. 1 ppm

4. 15 ppm

The correct answer is: 0.5 ppm

The permissible exposure limit (PEL) for chlorine gas vapor during a normal 8-hour workday and a 40-hour work week is set at 0.5 parts per million (ppm). This limit is established by organizations such as the Occupational Safety and Health Administration (OSHA) to ensure worker safety. Chlorine is a toxic gas that can irritate the respiratory system, and prolonged exposure to even low concentrations can pose significant health risks. By setting the PEL at 0.5 ppm, regulatory bodies aim to minimize the potential for adverse health effects while still allowing workers to perform their duties safely. It's important for operators in wastewater treatment to monitor and control chlorine gas concentrations to stay well within this limit, ensuring compliance with safety regulations and protecting both themselves and the environment. Understanding these limits is critical for effective workplace safety management.