How to Determine When a Chemical Needs Secondary Containment

Secondary containment prevents contamination of the environment, exposure to humans, and damage to property if there is a release from a container or tank containing hazardous material. Secondary containment needs to match the hazardous material it intends to contain if there is a break of the primary container or spill. Examples are a spill-tray, berm, spill pallets, double-skinned tank or a containment sump under storage and loading areas.

How do you know if secondary containment is required? If you have hazardous materials on site, you should think about their storage and secondary containment.

In this blog, we’ll walk through the key criteria to determine when a chemical needs secondary containment—and how to approach it effectively.

What Is Secondary Containment?

Secondary containment is part of your safety system, it is designed to catch leaks or spills from a primary chemical container, preventing hazardous substances from escaping into the environment.
Secondary containment is based on the hazards of the product, the volume that is stored, regulations in your area and the potential risk and consequences of a spill.

1. Review your Regulatory Requirements

Secondary containment is often required for hazardous substances that pose a risk to human health and safety, neighboring structures, or the environment. Begin by checking the regulations where you operate and their guidance on when secondary containment is required:

• Is it classified as a Hazardous Product? If the product is labelled as a hazardous product it will typically be regulated in your country. In Canada workplaces it is WHMIS. In the USA it is OSHA HazCom. In Europe it is REACH. If a product is classified as hazardous, it’s a signal to review the SDS and whether secondary containment is needed.
• What are the Environmental Laws? Regulations depend on jurisdiction and chemical type. In Canada, you will need to check the Canadian Environmental Protection Act, as well as provincial laws; for example, if you operate in Alberta you need to review the Environmental Protection and Enhancement Act. In the USA, the Environmental Protection Agency (EPA) under 40 CFR 264.175 mandates secondary containment for hazardous waste storage tanks and containers. There will also be state and in some cases municipal laws.

2. Identify the Chemical’s Hazards

What are the physical,health and environmental hazards of a product? How is it being stored? Is it segregated from incompatible products?
Review Section 2 of the Safety Data Sheet (SDS) for the product classifications and hazards. Section 7 of the SDS contains specific handling and storage recommendations. If the SDS recommends spill containment measures, secondary containment is advised.

3. How much of the hazardous product is on site?

The larger the quantity of a product stored, the greater the risk for a spill. You will need to check specific regulations for in your area but as a general guideline:

• If you're storing more than 23 gallons (87 litres) of a hazardous liquid, containment may be necessary.
• Bulk storage tanks, drums, or totes are typical candidates for secondary containment.
• Outdoor storage areas, where chemicals may be exposed to weather, often require secondary containment to prevent environmental discharge during rain, hail, temperature fluctuations, or snowmelt.

4. What is the Risk?

Chemical risk assessments are best practice to determine the potential harm from a leak or spill to your people, the environment and your facility.
Ask:

• What happens if this container leaks?
• Is the storage area near a drain, water source, or sensitive ecosystem?
• Is the flooring impervious or could it allow seepage?
• How long would it take for staff to detect and respond to a leak?

If the answer indicates any environmental or safety risks, secondary containment is the prudent choice.

5. Best Practices to Follow

• Contain 110% of the largest container or 10% of the total volume, whichever is greater.
• Use chemical-resistant materials compatible with the stored substance.
• Keep containment areas clean and free of debris or water accumulation.
• Include inspection and maintenance in your spill prevention plan.

Chemscape Can Help

Not sure where to start? At Chemscape, we specialize in SDS Management and Chemical Management Software to help organizations manage chemical risk and stay compliant, safe, and efficient.

Conclusion

Determining when secondary containment is needed comes down to a mix of regulation, chemical hazard, volume, and site-specific risk. Secondary containment protects your people, your operations, and the environment. If a spill or leak were to occur, the secondary defence system you have invested in will reduce the potential impact and harm.