Fire in commercial kitchen, caused by aggressive cleaning and strain on gas connector hose

Incident overview

Fire in kitchen that involved two gas appliances.

Regulated industry sector

Natural Gas System

Location

Fort St John

Investigation conclusions

Site, system and components

Commercial kitchen with various natural gas appliances installed under an exhaust hood canopy with a fire suppression system. Each appliance was connected with certified gas connectors. A moveable natural gas range installed on wheels was part of this system. A moveable commercial kitchen appliance connected with a certified gas connector must also have a non-combustible restraint device installed to avoid any undue stress on the gas connector when the appliance is being moved.

Gas connector — a factory-fabricated assembly consisting of gas conduit and related fittings designed to convey gaseous fuel from a gas supply piping to the gas inlet of an appliance. A gas connector is not intended for vibration isolation, nor expansion or contraction control.

Failure scenario(s)

The issue started with the gas appliance being pulled out too far and aggressively during cleaning operations, without proper restraints installed. This caused a gas leak on the connector hose, which was ignited from pilot flame positioned in close proximity to the leak.

Facts and evidence

Found all appliances without proper restraints installed.

Statements from manager and line cook, backed up by observed video at time of investigation.

-Clearly show at cleaning time, the appliances were moved aggressively to the furthest extent of the gas connectors.

-The gas leak on the connector ignited directly after cleaning crew pushed unit back in place, and went un-noticed till the cook arrived.

-Upon realization of fire, the cook instinctively pulled the unit out. This action caused the fire damaged gas connector to disconnect, thus creating a small blast and an increase in fire intensity.

-Directly after this occurred he engaged the fire suppression system, which successfully shut off gas supply and extinguished the fire.

Causes and contributing factors

It is very likely that the lack of appliance restraints, and the aggressive moving of the appliances by the cleaning crew, caused the gas leak in the connector. Which lead to the fire when the escaping gas was ignited by the pilot flame within close proximity to the leak.

Impact

• Injury
  • Qty injuries: None
  • Injury description: None
  • Injury rating: None
• Damage
  • Damage description: Minimal damage to commercial Gas Range, Deep Fat Fryer and surrounding area.
  • Damage rating: Minor

Incident rating

Minor