Kitchen Hood Fire Suppression in Bangladesh

Why can't you put out a fryer fire with water?

Cooking oil burns hotter than water boils. Water thrown onto it sinks, turns to steam instantly and throws burning oil out of the pan in a fireball. Modern vegetable oils also burn hotter than older animal fats, which is why older dry chemical hood systems often struggle with today's fryers.

Wet chemical agent works differently. It reacts with hot oil to form a soapy layer on the surface, a process called saponification, which seals in vapor and cools the oil so it does not reignite. Systems listed to UL 300 have been tested against modern cooking oils and appliance types.

Why does the duct matter as much as the stove?

Grease collects inside the hood plenum and exhaust duct over months of cooking. A small flare-up at the stove can pull flame into the duct, where it spreads out of reach and can travel to other floors. That is why the system protects three places at once: the appliances, the plenum and the duct entrance.

NFPA 96 covers the hood, grease filters, duct construction and cleaning. A suppression system cannot make up for a duct that has not been cleaned in years. We check duct condition during the survey and tell you if cleaning or duct repair should come first.

What happens when the kitchen layout changes?

Nozzles are aimed at specific appliances. When a kitchen adds a fryer, moves a wok range or swaps a grill, the coverage no longer matches. Any change to the cooking line should be checked against the system design before the new appliance is used, and we can re-aim or add nozzles as needed.

The same applies to hood or duct changes. A longer hood, a new exhaust fan or a rerouted duct can leave a section without a nozzle. During every six-monthly service we compare the cooking line with the drawing, and we update the drawing whenever the layout changes so the next technician works from the truth.