By Jason Treseder, Gas Engineer
ESV has issued a warning not to use butane
canister or “lunchbox” cookers after a
recent investigation found that a number
of these appliances are non-compliant
and may overheat, catch fire or explode.
All non-compliant butane cookers have
now been withdrawn from sale and a number
of unsafe models are being recalled due to
concerns relating to the internal overpressure
safety device, which can result in the butane
cartridge rupturing if it overheats.
What are butane cookers?
Butane cookers are small, portable gas
cookers that are supplied through disposable
butane cartridges. These appliances are portable,
inexpensive and are popular for cooking while
camping or undertaking outdoor activities.
However, this increase in popularity has brought
with it an increase in the number of incidents
involving these appliances that have been
reported to ESV and other gas safety regulatory
authorities over the past few years.
Investigations into the causes of these
incidents have found the use of large pots, frying
pans or barbecue plates, or the use of aluminium
foil or other activities that result in extra heat being
directed onto the gas cartridge are often involved.
Extra heat directed onto the gas cartridge causes
the pressure in the cartridge to increase. If the
heat source is not stopped the gas cartridge can
rupture resulting in an explosion and fire.
This risk is present with butane cookers as
the butane cartridge is located within the body
of the cooker and is relatively close to the burner
and the cooking vessel. To prevent this serious
safety issue all portable butane cookers are tested
to ensure under normal cooking conditions the
temperature of the cartridge does not increase
above ambient. Cookers are required to have
an overpressure safety device that shuts off gas
flow to the burner when the pressure inside the
cartridge reaches an excessive pressure.
This overpressure safety device consists of
a lever system attached to the gas valve such that
when the pressure inside the cartridge exceeds
a set value a pin will extend from the valve and
cause the gas cartridge to eject. This automatically
stops gas flow to the burner and allows the gas to
cool down. The pressure at which this device is
activated is well below the safe operating pressure
of the cartridge and if this device is operating
correctly the gas cartridge should never reach
a point when it is at risk of rupturing.
Due to the number of incidents occurring,
a review of compliance was conducted by ESV
and other gas regulatory authorities. This review
included sample testing of appliances currently
on the market to verify the correct operation of
the overpressure shutoff device.
The review found that a number of appliances
were fitted with safety devices that failed to
operate correctly, which means when the butane
cartridge is overheated the burner can remain
on and heat the gas to an unsafe pressure. In
extreme cases this can cause the gas cartridge
to rupture allowing unburnt gas to escape and
ignite, resulting in potential burns and injury to
Go to www.recalls.gov.au for details of of all
the models that are being recalled. If you would like
further information, contact ESV on 1800 652 563.
lick here to access the full list
of uncertified products that
should not be used