ONLINE SELF-STUDY
Compressed Gas Safety
Objectives
In accordance with OSHA's Hazardous Materials
standard (29 CFR 1910 Subpart H) it is important:
 To understand hazards associated with compressed
gases.


To learn how to effectively manage these hazards.
To learn about University policies regarding
compressed gas use.
About Compressed Gases
A compressed gas cylinder is any
cylinder specifically designed to contain
gases under pressure of greater than
one atmosphere, and having the
capability of dispensing the gas by the
means of a control valve mechanism to
assure the safe and proper use of the
gas at a point of operation.
About Compressed Gases
Compressed gases are hazardous
because they can cause fires, explosions,
oxygen deficient atmospheres, and toxic
gas exposures. In addition there are the
innate physical hazards associated with
cylinders under high pressure.
About Compressed Gases
A variety of compressed gases exist,
including flammables, non-flammables,
explosives, corrosives, as well as toxic
and oxidizing gases.
Reference labeling, safety data sheets
(SDS), and other safety literature for
specific hazard information.
About Compressed Gases
Special storage, usage, handling and
disposal procedures are necessary to
ensure the safety of employees using
compressed gases.
Also, compressed gases should be
included in chemical inventories . For
laboratories, their hazards should be
indicated on lab entrance signs.
Labels
All compressed gas cylinders must
bear labels that clearly identify the
contents.
Labels
No compressed gas cylinder should
be accepted that does not have its
contents identified by name.
If labeling on a cylinder is not clear
and the contents cannot be
identified, the cylinder should be
marked "contents unknown" and
returned directly to the
manufacturer.
Labels
Do not use the color of a cylinder
for identification. Color coding may
vary between suppliers. Also, do
not rely on labels on cylinder caps
because these caps are
interchangeable.
Storage
Store cylinders in designated areas where they will not be
knocked over or damaged by passing or falling objects.
Where cylinders are stored in the open, they should be
protected from accumulations of ice and snow and from the
direct rays of the sun. Full cylinders should be used in rotation
as received from the supplier.
Storage
Cylinders should not be subjected to a temperature above
125°F, nor should a flame ever be permitted to come in
contact with any part of a compressed gas cylinder.
Tanks should not be stored in cold rooms due to the lack of
exhaust in these spaces.
Storage
Compressed gas cylinders must be in an
upright position and supported at all times,
whether full or empty.
Be sure to secure the cylinder above its
center of gravity (~2/3 up the cylinder).
Do NOT secure cylinders by the valve.
Do NOT attempt to catch a falling cylinder.
Storage
Acceptable methods of support include:
 wall-mounted
or bench-mounted gas
cylinder brackets
 chains or belts anchored to walls or
benches
 dollies or carts designed for gas
cylinders and equipped with safety
chains or belts
Storage
The picture to the right is an example of
how NOT to secure a compressed gas
cylinder. This does not provide sufficient
support.
Securing cylinders individually is ideal. If
cylinders must be ganged together for
storage, only gang two cylinders together
at a time, if possible. If it is necessary to
gang more cylinders together please
contact EHS for advice.
Transporting Cylinders
Valve caps must be securely fastened before
cylinders are moved. Use appropriate dollies or
hand trucks to move cylinders weighing more than
50 pounds. Cylinders should never be rolled or
dragged.
Transporting Cylinders
Improper handling can seriously weaken the cylinder
and render it unfit for further use, or transform it into
a rocket having sufficient thrust to drive it through
walls. (You can watch the MythBusters make this
happen.)
Regulators and Gauges
Pressure regulators and gauges must
be compatible with the cylinder valves.
You may not use "cheaters" (adapters)
instead of the correct regulator and
gauge.
Regulators and Gauges
The Compressed Gas Association has
devised standard outlet connections to
prevent mixing of incompatible gases.
Outlet threads may vary in diameter.
Some are internal, some are external;
some are right-handed, some are lefthanded.
If a valve must be forced, it is a good
sign that the wrong valve is being
used.
Regulators and Gauges
All the connections should be checked
with a soap solution for leaks (except
for oxygen tanks). Never use oil or
grease.
Threads on cylinder valves, regulators
and other fittings should be inspected
regularly to ensure they are correct
and undamaged.
Regulators and Gauges
Cylinders should be visually inspected
to ensure that they are in safe
condition. If a leaking cylinder is
discovered, move it to a safe place (if
it is safe to do so) and contact EHS for
precautionary advice and disposal
assistance. You should also call the
vendor as soon as possible.
Do NOT attempt to repair a cylinder
or valve.
Special Notes
Lecture Bottles
Lecture bottles are small compressed
gas cylinders, typically 12-18 inches
long and 2-3 inches in diameter.
Lecture bottles should be secured
during use. All lecture bottles
containing hazardous gases should be
used in a chemical fume hood. These
cylinders are typically non-returnable.
Special Notes
Hydrogen and Acetylene
Hydrogen is a colorless, odorless and
tasteless gas. Acetylene is a colorless
gas with a distinctive garlic-like odor.
These are both flammable gases. A
mixture of either gas with oxygen or air
in a confined area will explode if
ignited by spark, flame or other source
of ignition.
Special Notes
Hydrogen and Acetylene
Post all hydrogen and/or acetylene
storage and usage locations with
permanent placards that read:
HYDROGEN/ACETYLENE
- FLAMMABLE GAS - NO SMOKING - NO OPEN FLAMES -
Special Notes
Oxygen
Oxygen is a colorless, odorless, and
tasteless gas. It can greatly accelerate
combustion. These cylinders should never
be stored near flammable gases.
Greasy or oily material should never be
stored around oxygen. Also, do not use
soap based leak detector compounds on
the connection threads of an oxygen
cylinder.
Special Notes
Corrosive Gases
Corrosive gases can burn and destroy
body tissues on contact. Corrosive
gases can also attack and corrode
metals. Common corrosive gases
include ammonia, hydrogen chloride,
chlorine and methylamine.
Special Notes
Cryogenic Gases
Cryogenic gases are extremely cold and
accidental contact with eyes or skin may
cause severe frostbite.
Personal protective equipment (PPE) must be
worn by employees who handle and use
cryogenic gas cylinders. This includes gloves
constructed of insulating materials, rubber
aprons, safety glasses or goggles and a
complete face shield.
Special Notes
Cryogenic Gases
Proper PPE:
Special Notes
Cryogenic Gases
Tremendous pressures can result in enclosed
spaces as the liquid converts to gas. For
example, one cubic centimeter of liquid
nitrogen will expand to 700 times this
volume as it converts to its gaseous state.
For this reason, asphyxiation can be an issue.
Depending on the size of a room and volume
of gas, an oxygen monitor may be needed.
Special Notes
Dangerous Gases
Any gases that may cause significant acute health
effects at a low concentration are considered
dangerous gases.
Cylinders of dangerous gases, such as ammonia,
carbonyl sulfide, hydrogen cyanide, hydrogen
sulfide, methylamine, and nitric oxide, must follow
the University's Dangerous Gas Policy.
Disposal
There are two general types of compressed
gas cylinders:
 returnable (owned by the gas supplier,
rental fee charged to the University)
 non-returnable
Most suppliers will accept the return of their
cylinders even if they are not empty.
However, suppliers will not accept nonreturnable cylinders under any circumstances.
Lecture bottles are typically non-returnable.
Disposal
Disposal of non-returnable cylinders
containing highly toxic or reactive gas can be
very expensive. Therefore, purchase
compressed gases in returnable cylinders if
available. If non-returnable cylinders are the
only alternative, be prepared to pay for the
cost of disposal. To dispose of these cylinders
request a waste pickup online through EHS.
Review


All compressed gas cylinders must bear labels
that clearly identify the contents.
Compressed gas cylinders must be in an upright
position and supported at all times, whether full
or empty. Acceptable methods of support
include:
 wall-mounted
or bench-mounted gas cylinder
brackets;
 chains or belts anchored to walls or benches; and,
 free-standing dollies or carts designed for gas
cylinders and equipped with safety chains or belts.
Review


Gas cylinders must have the valve protection
cap in place except when in use.
Use appropriate dollies or hand trucks to move
cylinders weighing more than 50 pounds.
Review


Pressure regulators and gauges must be compatible
with the cylinder valves. You may not use "cheaters"
(adapters) instead of the correct regulator and
gauge.
Reference labeling, safety data sheets (SDS), and
other safety literature for specific hazard
information.