Compressed Gas Cylinders
The outward appearance of
a compressed gas cylinder is deceptive. The average standard size cylinder
is pressurized at 2,200 pounds per square inch. These cylinders are
safe under normal use; however, serious accidents have resulted from
the misuse, abuse, or improper handling of compressed gases.
The following principles
must be adhered to for safe storage, use, and transportation of compressed
Cylinder Use, Storage, and Transport
- Use cylinders in an upright
position, unless equipment manufacturer provides specific instructions
- Turn all valves off when
not in use.
- Do not modify relief valves.
- Know the contents, properties,
and health hazards associated with the contents. Contents must be
- Notify distributor immediately
of any problems in the operation or condition of the cylinder (e.g.
- Ensure all hardware connecting
the cylinder to receiver is compatible with the pressure and contents
to which it is exposed always use the correct gauge for the pressure
and chemical to which it is exposed.
- Select the smallest reuseable
cylinder compatible with the need.
- Always release pressure
from regulator before disconnecting.
- Emergencies: in the event
of a cylinder emergency such as a significant leak, evacuate the area,
shut the door, and call 911.
- Always return compressed
gas cylinders when finished. Vendors charge "demurrage fees" (rental)
on compressed gas cylinders. These fees can often add up to exceed
the purchase price of the gas if the cylinders sit for extended periods
in storage. If cylinders cannot be returned to supplier, contact Environmental Management (859) 323-6280 for instructions.
- The valve protection cap
should be left in place until the cylinder is secured and ready for
use. Never struggle with a cylinder cap or use a screw driver to remove
a cylinder cap. Do not drop cylinders or allow them to be struck with
- Secure cylinders in an
upright position with proper chain, stand, or strap. Stored cylinders
must have the valves closed and the valve covers must be in place.
- Never store cylinders
of flammable gases (empty or full) near cylinders of oxygen or other
oxidizers. A minimum separation of 20 feet or specially designed separation
wall must be maintained. When practical, store cylinders a minimum
of 20 feet from flammable liquids and away from sources of heat. If
this is not practical, consult University Fire Marshal 257-6326 for
- Never store cylinders
in a means of egress.
- Clearly mark "empty" cylinders
with tag or sign. Writing "MT" in chalk or on label is not acceptable.
Separate "empty" and "full" cylinders to avoid confustion and do not
store empty cylinders in your laboratory.
- Cylinders should not be
placed, stored or used on sides unless recommended by manufacturer.
- Cylinders must be hydrostaticly
tested every 10 years. Note the last test date on top of the cylinder.
Notify the supplier immediately if outdated cylinders are identified.
- Keep amount of flammable
gases to a minimum. The number of flammable gas cylinders (10"x50")
must not exceed 3 cylinders per 500 square feet in a non- sprinkled
building or 6 cylinders per 500 square feet in a sprinkled building.
- Never rely on color-coding
as a way to identify the compressed gas cylinder. Color codes are
for the owner's convenience.
- Transport cylinders in
an upright position.
- Never roll or drag full
or empty cylinders. Preferred transport method is to secure cylinders
(with valve covers in place) to a hand truck or similar mode of transport.
- Do not move a cylinder
that has a regulator on it even if main tank valve is off.
- Treat "empty" cylinders
with same respect as "full" cylinders.
- Transport of cylinders
via stairs is discouraged unless other means of upper floor access
is not available. When transporting cylinders via stairs, the cylinders
must be capped and secured in an upright position to a hand truck
suitable for use on stairs.
Extremely Toxic and Pyrophoric
- Extremely toxic and/or
pyrophoric gases require special care for use, storage, and transport.
This may include special gas-monitoring systems, alarms, storage cabinets
(or other ventilation devices), and/or special transport procedures.
- Notify OH&S
before purchasing or using extremely toxic and/or pyrophoric gases.
(See attached compressed gas cylinder registration
form.) OH&S will assist in the evaluation of special facility
needs and training requirements for using these materials.
The following gases
or any other gas that has a threshold limit valve (TLV) less than 1
part per million (PPM), a flash point less than 0 F, or is pyrophoric
should be registered with OH&S before purchase or use:
- Arsine - extremely toxic
(TLV 0.05 PPM) and extremely flammable
- Chlorine - extremely toxic
(TLV 0.5 PPM)
- Diborane - extremely toxic
(TLV 0.1 PPM) and extremely flammable
- Germane - extremely toxic
(TLV 0.2 PPM)
- Hydrogen Selenide - extremely
toxic (TLV 0.05 PPM) and highly flammable
- Hydrogen Sulfide - extremely
toxic (TLV 10 PPM) and very offensive odor
- Mercaptans (thiols) -
extremely toxic (TLV's vary 0.5 PPM) flammable, offensive odor
- Phosgene (carbonyl chloride)-
extremely toxic (TLV 0.1 PPM)
- Phosphine - extremely
toxic (TLV 0.3 PPM)
- Silane - pyrophoric
- Stibine - extremely toxic
(TLV 0.1 PPM)
- Any chemical that does
not have a TLV.
Reviewed by Chemical Safety Committee
June 7, 1996.
Approved by General Safety Committee September 17, 1996.
Revisions approved by General Safety Committee December 10, 1996.