| One of the traits that make propane so
well suited to RV use is its forgiving nature. In gaseous form,
propane is only combustible within a narrow range of air/fuel
concentrations (2.5% - 9.5% by volume), making it considerably
harder to accidentally ignite than many other fuels. Also, even
though pure propane has very little odor, virtually all fuel-grade
propane includes an “odorant” (ethyl merchantman) that makes it
easily recognizable, even in very low concentrations (0.5% by
volume). These inherent safety characteristics allow most propane
leaks to be quickly identified and fixed without incident.
However, safe as this gas is, there are still ways of misusing it.
Overfilling remains one of the most common culprits, even though
the increasing use of Overfill Prevention Devices is reducing this
trend. There are still plenty of non-OPD tanks in the field, and
as OPD tanks become the rule rather than the exception, the chance
of overfilling a conventional tank due to operator inattention
decreases considerably.
By design, approximately 20% of the interior space in all
propane tanks, OPD and otherwise, is reserved for expansion to
safely accommodate the 1.5% increase in volume that propane
experiences for every 10 degree Fahrenheit temperature increases.
In an overfilled tank, insufficient space may remain as the
propane warms up, expelling gas and/or liquid forcefully through
the safety relief valve.
Because this venting is unpredictable and could occur in
hazardous location, it is essential that the tank be refilled
properly. Many portable tanks are equipped with fixed level gauges
that can be used to determine safe fill levels. However, weighing
the tank is still the most accurate method, eliminating any chance
of error that might be caused by replacing the original fixed
level gauge with one designed for a different tank size or shape.
Note that the float-type gauges normally used for determining the
amount of propane in the tank are neither reliable nor accurate
enough to be used for determining safe fill levels.
Also, bear in mind that the OPD is intended to provide
supplemental protection against tank overfilling, not to serve as
the sole means of overfill prevention. The presence of an OPD
doesn’t relieve the refiller from the duty of determining the
tank’s proper fill volume, either by weight or by using the fixed
level gauge.
The next most common hazard is caused by storing, transporting
or repairing propane tanks in enclosed areas. In addition to
living areas, this also includes enclosed garages, storage sheds
and passenger vehicles.
There are plenty of other propane safety tips, ranging from the
subtle to the obvious: Keep tanks away from heat sources.
Always store and transport unused tanks with the service
valve closed and plugged.
Regularly inspect “pigtails” and other flexible hoses for
signs of cracks or abrasion. Replace them before they become old
enough to develop leaks.
Never use a flame to check for propane leaks. Approved leak
detectors are available; in a pinch, soapy water can be
substituted.
Never use pliers or a wrench to close the service valve or
fixed level gauge. If hand tightening or a screwdriver won’t
suffice, repair is in order.
Make certain that tanks are secured in place before any trip,
and only transport or operate them in their intended positions.
Never lay an upright cylinder on its side because it could
expose the safety relief valve to liquid propane.
When first using a refilled tank, slowly open the valve all
the way, listening to the regulator. A continuous hiss may
indicate a leak somewhere in the system.
Many propane regulators have a “right side up” orientation
that must be observed to prevent malfunctions, which could
result in dangerously high or low pressures being delivered to
appliances.
RV propane tanks should be located in unlocked compartments,
except in situations where contact with children is likely. During
an emergency, this allows anyone to quickly shut off the propane,
even if the RV’s owner isn’t present.
Because propane is heavier than air, any propane alarm should
be installed near the floor. This helps minimize its response
time.
To reduce the chance of accidentally opening the service valve
before removing a POL fitting , it is common practice to leave the
valve a small fraction of a turn short of fully open whenever the
tank is in use. This removes any doubt as to whether the valve is
fully open or closed, requiring several complete turns to close
it.
Always shut off the propane before driving through tunnels,
before moving the RV indoors for service or storage, or before
transporting it in an enclosed ferry compartment.
When refilling tanks installed in vehicles, a temporary ground
clip should be connected to the tank for the duration of the
filling process, to eliminate sparks caused by static electricity.
Never use a cylinder if it shows signs of dents, gouges,
bulges, fire damage, corrosion, leakage, excessive rust or other
forms of external damage.
If you smell propane gas, follow these emergency steps:
Put out smoking materials and other open flames.
Don’t operate electric switches, light matches or use a
phone. Any spark or flame in the area could ignite the gas.
Immediately get everyone out of the RV, vehicle or other
enclosed area.
Close all gas tank or cylinder supply valves.
Do not re-enter the area. Use a neighbor’s telephone to call
a trained propane service person and/or the fire department.
Let the service person or firefighters check for propane gas
leaks. Have them air out the area before you return.
Have properly trained propane service people repair any leak,
then check and relight pilot lights for you.
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