Commercial Kitchen Fire Suppression
Required over grease-producing cooking, and only as good as its last six-month service.
Restaurant and institutional kitchens are one of the few places where the codes are completely clear: a hood over grease-producing appliances needs a listed fire suppression system, the system has to meet UL 300 in the US (ULC/ORD-C1254.6 in Canada), and it has to be inspected every six months. The system is a pre-engineered wet-chemical unit that sprays a potassium-salt agent onto the appliances and into the duct, shuts off the fuel, and is backed up by a Class K portable extinguisher on the wall. You buy it from an authorized distributor of the brand, who designs, installs and services it.
Systems and products
2 guides · price bands $ to $$$$
Commercial Kitchen Hood Wet-Chemical System (UL 300)
A pre-engineered system inside the exhaust hood sprays potassium-based wet chemical onto the appliances, plenum and duct when fire is detected, and shuts off the gas or power to the cooking line. It is required over most grease-producing commercial cooking.
Class K Wet-Chemical Extinguisher for Commercial Kitchens
A portable wet-chemical extinguisher required near commercial cooking appliances that use vegetable or animal oils. It is a backup to the hood suppression system, not a replacement.
Before you buy
- Systems older than the UL 300 standard (1994) were designed for animal fats, not today's high-temperature vegetable oils. If a kitchen still has one, replacing it is not optional in most jurisdictions.
- Rearranging or swapping appliances under the hood can leave them outside nozzle coverage. Tell your service company before the line changes, not after.
- Semi-annual inspection is required, and fusible links have to be replaced on a fixed schedule. Keep the tags; inspectors and insurers ask for them.
- The Class K extinguisher is a backup for after the system has fired, not a substitute for it.
- Hood and duct cleaning is a separate trade and a separate schedule. Grease in the duct is what turns a pan fire into a building fire.