What is the potential risk?

Workers who are exposed to high levels of chlorine gas may be at risk of immediate injuries including damage to the eyes, irreversible lung damage, or even death. Workplaces that transport, store, or use chlorine may experience an accidental release of chlorine, potentially exposing workers to this toxic process gas.

Chlorine is a yellow-green gas with a strong bleach-like odour. It is commonly used as a process gas in manufacturing or as a disinfectant in water treatment applications. During transport and storage, chlorine is compressed into a liquid form. If there is a leak or damage to the storage or process equipment, chlorine gas could be released, potentially putting workers or members of the public at risk of adverse health effects.

There have been incidents of chlorine release in B.C. that have resulted in worker injuries.

Workers in workplaces that may be using chlorine as part of their manufacturing processes or as a disinfectant may be at risk of exposure to chlorine. These workplaces may include paper manufacturers, public swimming pools, drinking water treatment, and waste water treatment plants.

What industries may be at risk?

• Paper product manufacture
• Transportation and related services
• Local government

How can I reduce the risk in my workplace?

As an employer, you need to know if there is the potential for the risk identified in this advisory to be present in your workplace. It’s your responsibility to regularly inspect your workplace, and to ensure that your safety procedures and practices control the risk. The following information highlights some of the sections of the Occupational Health and Safety (OHS) Regulation and Guidelines that are most relevant to this risk.

Sections 6.116–6.132 of the OHS Regulation cover the requirements for toxic process gases, one of which is chlorine.

The Regulation requires that employers implement an exposure control plan meeting the requirements of section 5.54.

The BC Fire Code and Part 3 of the BC Building Code also place additional duties on the employer regarding the control of risks relating to the storage and handling of flammable substances.

Guidelines G6.116 to G6.127 also address toxic process gases.

Where can I find resources?

You can access the following resources:

• Book: Chlorine safe work practices (WorkSafeBC)
• Book: PoolSafeBC Best Practices Guide (BC Recreation and Parks Association)