EXTINGUISHING THE FLAME
NEVER interchange hoses, regulators, or other
apparatus intended for oxygen with those intended for
To extinguish the oxyacetylene flame and to
acetylene.
secure equipment after completing a job, or when
Keep valves closed on empty cylinders.
work is to be interrupted temporarily, you should take
the following steps:
Do NOT stand in front of cylinder valves while
opening them.
1. Close the acetylene needle valve first; this
extinguishes the flame and prevents flashback.
When a special wrench is required to open a
(Flashback is discussed later.) Then, close the oxygen
cylinder valve, leave the wrench in position on the
needle valve.
valve stem while you use the cylinder so the valve can
be closed rapidly in an emergency.
2. Close both the oxygen and acetylene cylinder
valves. Leave the oxygen and acetylene regulators
Always open cylinder valves slowly. (Do NOT
open temporarily.
open the acetylene cylinder valve more than 1 1/2
turns.)
3. Open the acetylene needle valve on the torch
and allow gas in the hose to escape for 5 to 15
Close the cylinder valves before moving the
seconds. Do NOT allow gas to escape into a small or
cylinders.
closed compartment. Close the acetylene needle
valve.
NEVER try to force unmatching or crossed
threads on valve outlets, hose couplings, or torch
4. Open the oxygen needle valve on the torch.
valve inlets. These threads are right-handed for
Allow gas in the hose to escape for 5 to 15 seconds.
oxygen and left-handed for acetylene. The threads on
Close the valve.
acetylene cylinder valve outlets are right-handed, but
5. Close both oxygen and acetylene cylinder
have a pitch that is different from the pitch of the
regulators by backing out the adjusting screws until
threads on the oxygen cylinder valve outlets. If the
they are loose.
threads do not match, the connections are mixed.
Follow this procedure whenever your work will
Always use the correct tip or nozzle and the
be interrupted for an indefinite period. If you stop
correct pressure for the particular work involved.
work for only a few minutes, you don't need to secure
This information should be taken from tables or
the cylinder valves and drain the hoses. However, if
worksheets supplied with the equipment.
you stop for an indefinite time, follow the entire
Do NOT allow acetylene and oxygen to
extinguishing and securing procedure. For overnight
accumulate in confined spaces. Such a mixture is
work stoppage in areas other than the shop, it is a
highly explosive.
good idea to remove the pressure regulators and the
torch from the system. Double check the cylinder
Keep a clear space between the cylinder and
valves to make sure they are closed securely.
the work so the cylinder valves may be reached
quickly and easily if necessary.
SAFETY: OXYACETYLENE EQUIPMENT
When lighting the torch, use friction lighters,
When you are heating with oxyacetylene
stationary pilot flames, or some other suitable source
equipment, you must observe certain safety
of ignition. The use of matches may cause serious
precautions to protect personnel and equipment from
hand burns. Do NOT light a torch from hot metal.
injury by fire or explosion. The precautions that
When lighting the torch, open the acetylene valve first
follow apply specifically to oxyacetylene work.
and ignite the gas with the oxygen valve closed. Do
NOT allow unburned acetylene to escape into a small
Use only approved apparatus that has been
or closed compartment.
examined and tested for safety.
When extinguishing the torch, close the
When you use cylinders, keep them far enough
acetylene valve first and then close the oxygen valve.
away from the actual heating area so they will not be
Do NOT use lubricants that contain oil or
reached by the flame or sparks from the object being
grease on oxyacetylene equipment. OIL OR
heated.
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