CTSF/GAS/LPGA/1.00
Liquified
Petroleum Gas (LPG)
Liquefied petroleum gas (also
called LPG, LP Gas, or autogas)
is a mixture of hydrocarbon
gases commonly used as a fuel
for many mobile or remote
installations requiring a gas
supply.
The two most common varieties of LPG
include mixes that are primarily propane
(stored in red cylinders) and mixes that
are primarily butane (stored in blue cylinders) – please see the illustration below.
to between 80% and 85% of their capacity. Propane is a hotter gas than both butane and natural gas, and will still “boil” at
temperatures well below freezing.
The boiling point of butane is only just
below 0°C, telling us that at temperatures
below this the gas will not boil, therefore
will remain in a liquid state in the bottle,
effectively unusable until the temperature
increases. Propane, however will operate
at temperatures less than -40°C, hence is
quickly becoming the LPG of choice for
commercial catering applications.
with gas. It cannot be stressed enough
that whilst any gas can be dangerous if
not used correctly, propane operates at
2.5 times the temperature of natural gas
and at nearly twice the pressure.
Safety Considerations
LPG is a highly flammable fuel gas, and is
about 50% heavier than air. This presents
an additional safety problem not associated with natural gas –the operator may
not smell any leak until such a time as the
room fills up with gas, unlike natural gas
which is lighter than air and will be noticed almost immediately.
LPG can therefore accumulate at ground
level and in low lying areas. If LPG collects in a low area, such as a drain, cellar
or basement, it could ignite resulting in a
fire or explosion.
An LPG leak can go unnoticed for some
time and is therefore more likely to accumulate, increasing the potential danger.
This build-up may be some distance away
from the pipe. It is therefore important to
ensure that all LPG pipework is adequately
inspected and maintained.
At normal temperatures and pressures,
LPG will evaporate. Because of this, LPG is
supplied in pressurised steel bottles.
In order to allow for thermal expansion of
the contained liquid, these bottles are not
filled completely; typically, they are filled
Rapidly “boiling” propane cools cylinders
and pipe work to as low as -42°C and can
Because of the differences in the stor- often cause frostbite if touched.
age & operating pressures of natural gas,
propane & butane, not all gas fittings are WE HOPE THIS GUIDANCE HAS BEEN OF
interchangeable. For this reason it is im- ASSISTANCE AND IF YOU CONSIDER THAT
portant that a suitably competent CORGI WE COULD HELP FURTHER PLEASE DO NOT
engineer be sought for all work required HESITATE TO CALL.
Catersafe, 6 Dalcross Street, Roath, Cardiff, CF24 4UB
Tel: (029) 20 498361