Almost half of all household fires are caused by cooking situations gone awry and in 2011 over 5,000 people were injured by flames in the kitchen. You might also be surprised to learn that not all kitchen fires will trigger a fire alarm in an apartment style residential building. It is a fairly common occurrence for fire alarm systems to not activate when a burning material is left on a stove inside a unit. There can be a high amount of visible smoke yet the fire alarm devices do not activate in the hallway.
How is this possible? We turned to our fire safety experts for the answers:
Explanation 1: The smoke that is generated by a smoking pot is very high in moisture and that moisture may in fact prevent the smoke from reaching the ceiling where the detectors are located. By the time it goes out in to the hallway, the moisture has cooled the smoke off to the point where the detector does not recognize it as smoke
Explanation 2: The smoke detectors used on a fire alarm system are typically ionization smoke detectors. These detectors are known to respond much faster to open flame fires where there is very little smoke but the smoke contains a lot of “hot” ash or invisible products of combustion. Photoelectric detectors are much better at detecting slow smouldering fires where there is a lot of visible smoke. Both smoke detectors are ULC listed and must respond within a certain range in order to get listed. The best fire alarm design would incorporate both kinds of devices but most systems uses ionization devices.
It is important to keep in mind that many kitchen fires are contained to the pot of their origin and will often not spread beyond the burner. In the case where the flames are contained to a single pot, there is little risk of life-threatening situations. If the fire were to spread beyond the original pot and to the surrounding cupboards or drywall, this is when your smoke alarm would almost certainly respond. ULC performs exhaustive testing to ensure that all smoke alarms sold in Canada meet the highest standards and would allow enough notice for you to evacuate your premises in the event of a life threatening fire as long as you respond as soon as the device activates. For more tips on how to extinguish kitchen fires before they get out of control, check out our Kitchen Fires Are Too Hot To Handle Infographic.