Understanding Hazmat Storage Fire Protection Ratings

Proper storage of hazardous materials (hazmat) ensures the safety of personnel, your facilities, and the environment. Storing flammable materials in a chemical storage locker with the right fire rating level can prevent catastrophe. Ensure you understand hazmat storage fire protection ratings to choose effective, compliant units for your business.

Fire Rating Levels

Hazmat storage containers can be non-fire-rated or rated for a specified number of hours. To determine the required fire rating for your storage circumstances, consult the Occupational Safety and Health Administration (OSHA), the National Fire Protection Association (NFPA), and your local fire marshal.

At American Hazmat Rentals, we offer storage lockers rated for one, two, three, or four hours of fire protection. The most common types are the two-hour and four-hour fire-rated options.


Non-fire-rated hazmat storage lockers are appropriate for holding non-flammable hazardous chemicals, such as:

Oil-based paints are flammable and subject to OSHA rules for flammable liquids. However, latex-based paints are not flammable.


Use a two-hour container to store flammable and combustible chemicals within 10 to 30 feet of property lines and occupied facilities. UL is a global testing and certification company that performs fire-resistance tests on products. A two-hour rated structure has wall, floor, and ceiling assemblies that maintain an acceptable temperature in the container for two hours as determined by UL.


Use a four-hour container to store flammable and combustible chemicals within 10 feet of property lines and occupied facilities. The extended resistance to fire allows for a more controlled and efficient response.

Optional Fire Suppression Systems in Storage Units

Some hazmat containers have a fire suppression system that will activate if contents are ignited. Dry chemical fire suppression systems prevent fires from growing out of control.

American Hazmat Rentals equips some container units with the Pyro-Chem MONARCH dry chemical fire suppression systems. These systems meet UL and NFPA approvals and standards and provide automatic detection and actuation controls for 24-hour protection.

Temperature detectors monitor ambient temperature and alert the system if the temperature exceeds the pre-set amount. The system’s control head discharges the dry chemical agent, which works to suppress the fire by smothering it and absorbing heat.

Chemical Storage Ventilation

Mechanical and passive ventilation systems protect personnel and stored chemicals from vapor buildup. For flammable hazmat storage, containers must meet the NFPA’s ventilation requirements to safely store chemicals that produce flammable, explosive, and toxic fumes by regularly changing the air.

Ventilation systems do not just help prevent fires. If a fire breaks out, the system is engineered to minimize spread. In extreme fire exposure, vents may collapse and create an opening for the fire to escape the unit and spread. To prevent this problem, flammable hazmat storage ventilation systems have fire dampers that automatically close in extreme heat to restrict the flames.

More Fire Safety Features

Additional fire safety features can make your chemical storage container more secure. These features may come standard with your unit, or you may add them in a custom order.

Spill Containment Sump

Spills and leaks are dangerous in chemical storage areas. They can cause fires, explosions, and adverse health effects, such as delayed cancer that appears years after initial exposure.

A spill containment sump is a secondary containment system that collects and contains leaked or spilled chemicals. The system prevents chemicals from escaping the unit and contaminating the environment. Capturing the chemicals simplifies the cleanup process.

Explosion-Proof Lighting

The NFPA mandates that all lighting equipment in hazardous locations must be explosion-proof. Explosion-proof lighting fixtures can contain sparks that could otherwise ignite flammable and explosive gases in the air. The lighting casement is usually made from steel or aluminum, and the light lens resists cracking to prevent leaks.

Regulating Authorities

Fire-rated chemical storage buildings are crucial for ensuring your business’s safety, security, and compliance. Solid steel construction and industrial-grade, fire-resistant insulation maximize durability and fire protection. Use fire-rated hazmat storage to contain flammable liquids and materials, corrosives, and combustibles.

OSHA creates and enforces hazardous materials storage regulations. The NFPA also creates flammable storage limits and requirements, and your local fire marshal enforces fire code hazmat compliance.

The Right Fire Protection System

OSHA, the NFPA, and fire marshals regulate the storage of flammable hazardous materials in commercial, warehouse, industrial, and other business operations. You can start determining which fire-rated system your operation will require by identifying the materials you will store and grouping them based on the applicable Material Safety Data Sheets (MSDS) required by OSHA.

You should also contact your local fire marshal to understand your responsibilities and options. Fire marshals investigate the cause and origin of every major or suspicious fire to determine if the fire was intentionally set or caused by poor design. Discuss your materials with the fire marshal to ensure compliance.

The Chemical Storage Setback

A setback is the distance between chemical storage lockers and employees and property. Setbacks shield environmentally sensitive areas, such as water sources, vegetation, and wildlife habitats. The setback mitigates fire hazards by delaying the spread of flames and heat transfer, giving personnel time to initiate emergency protocols to minimize damage.

Consider the setback when choosing chemical storage containers. The right fire-rated units are a crucial aspect of safely handling and storing flammable, hazardous chemicals. If a leak, spill, or fire occurs, the appropriate fire-rated storage—based on the materials and setback—will reduce the chance of the hazardous substances reaching critical areas, improving containment.

Consult with your local fire authority to understand ordinances and zoning regulations for determining appropriate setbacks. Knowing the local fire code will help you maintain compliance.

Shop With a Reputable Hazmat Storage Company

Understanding hazmat storage fire protection ratings is critical for protecting employees and the environment and ensuring regulatory compliance. Consider the types of materials you store and the container setback you need to determine the regulations that apply to your circumstances.

Fire protection systems can be rated for one, two, three, or four hours of protection. Fire suppression systems, chemical storage ventilation, spill containment sumps, and explosion-proof lighting are other accessories that help protect your storage unit.

Ensure the highest safety and quality standards by shopping with a reputable hazmat storage supplier. American Hazmat Rentals has the expertise to deliver compliant storage units that meet the highest industry standards. Shop with us for flammable paint storage in various sizes and configurations to meet the needs of your site.

Understanding Hazmat Storage Fire Protection Ratings

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