We all know the UL 300 story. In 1994, The UL 300 standard for restaurant fire suppression systems was revised to address real-world fire risks in commercial kitchens.

UL realized that changes in commercial kitchens had dramatically increased the risk and severity of kitchen fires. Thus existing testing protocol had to be revised to reflect changes such as:

• • • The use of vegetable oil instead of animal fat and,
    • The use of high-efficiency appliances that heated much quicker and cooled much slower.
    • UL also added more realistic testing methods.
    • Commercially available appliances had to be used.
    • Pre-burn times were increased to more realistically reflect automatic detection response time, and,
    • The appliance heat source had to remain on until the system activated.
    • Splash testing of appliances was also added as a necessary safety precaution.

Effect of UL 300 Fire Suppression Standards have on existing systems

Pre-UL 300 wet chemical systems had to be significantly enhanced to meet the new requirements. For example, friers required 5 times more agent to extinguish and prevent re-ignition.

Overall, about 25% more agent was necessary to meet the more stringent testing requirements. Dry chemical systems did not meet these requirements. They failed to prevent re-ignition and they failed to pass the new splash testing requirements.

This is a UL 300 wet chemical system discharging. Notice the chemical reacting with oil to form a blanket of saponification. This blanket prevents re-ignition.

The risk of not upgrading dry chemical restaurant systems can no longer be ignored.

The time to upgrade is now.