What
are the occupational hazards of propane fuel?
 Exposure
to high levels of propane fuel occurs generally only while
filling tanks or from a leak from the tank or fuel delivery
system. Propane gas is heavier than air; therefore leakage
from a vehicle parked or stored near an unventilated pit or
a lower level room is a hazard.
Brief exposures to concentrations of propane
up to 10,000 parts propane per million parts of air (ppm)
do not cause any symptoms in humans. Exposures to very high
concentrations of propane (100,000 ppm) can produce slight
dizziness after a few minutes of exposure. At extremely high
concentrations (several hundred thousand parts per million),
propane acts as an asphyxiant by displacing oxygen. This means
one could suffocate if exposed to high enough concentrations
of propane because it dilutes the oxygen in the air.
There have only been a very few studies of
accidental overexposure to propane; victims reported symptoms
of disorientation, excitation, headache and vomiting.
Propane gas is very flammable and should
be considered as a fire hazard.
What are hazards of propane combustion products?
Complete combustion of propane results in
the formation of carbon dioxide and water vapour. Carbon monoxide
is a by-product of combustion when there is not enough oxygen
to burn the propane completely.
Carbon monoxide and carbon dioxide are hazards
when propane-powered equipment is used in enclosed, poorly
ventilated areas. Symptoms of carbon monoxide and carbon dioxide
overexposure include headache, fatigue, dizziness and nausea.
Carbon monoxide is a toxic gas that interferes with the ability
of the red blood cells to carry oxygen. Exposure to very high
concentrations of carbon monoxide, (more than 4,000 ppm),
can result in coma or death.
Because carbon dioxide is an asphyxiant gas,
exposure to extremely high concentrations, (above 100,000
ppm), can result in death. Such life-threatening concentrations
are very unlikely to occur in most workplace situations. However,
symptoms of headache, fatigue and dizziness may show that
there is inadequate ventilation in the workplace. The frequency
of complaints of these symptoms increases as the carbon dioxide
levels increase above 800-1,000 ppm.
How can you control the exposure to propane
and its combustion products?
Regular maintenance, tuning of propane-powered
engines and inspection of vehicle exhaust systems for leaks
keep the exposure to a minimum.
To control exposure to propane during refueling
the generally recommended procedures include:
- storage, refilling and handling of liquid propane fuel
by qualified or trained personnel, and
refueling or exchanging removable propane cylinders outdoors
or in well ventilated areas, away from sources of ignition.
- The refueling area should be equipped with a fire extinguisher.
When using propane-powered equipment indoors,
ensure that there is adequate ventilation in the workplace.
Some jurisdictions recommend specific ventilation rates. Some
countries have recognised the dangers and have even specified
the rate at which air should be purified in terms of X cubic
feet per minute.
Safe usage >>
|
