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United States Department of
Transportation
Research and Special Programs Administration
[Notice 98-12]
Safety Advisory; High Pressure
Composite Cylinders
AGENCY: Research and Special
Programs Administration (RSPA), DOT.
ACTION: Safety Advisory Notice.
SUMMARY: RSPA is alerting
persons who own, use or are responsible for the maintenance
of composite cylinders to a hazard. Damage may occur when a
composite cylinder comes in contact with strong cleaners or
other strong corrosive agents. RSPA is aware of ruptures
involving two DOT-E 8059 composite cylinders made with
aluminum liners and wrapped with "S glass" fibers. The
probable cause of both cylinder failures was
stress-corrosion cracking of the fiberglass overwraps as a
result of exposure to a strong corrosive agent.
FOR FURTHER INFORMATION CONTACT:
Cheryl West Freeman, Office of Hazardous Materials
Technology, Research and Special Programs Administration,
U.S. Department of Transportation, 400 Seventh Street, S.W.,
Washington, D.C. 20590-0001; Telephone (202) 366-4545
SUPPLEMENTARY INFORMATION: RSPA
investigated two failures involving self-contained breathing
apparatus (SCBA) cylinders manufactured by EFI Corporation
under exemption, DOT E-8059. The first failure occurred in
March 1996 at the Humboldt (California) Fire Protection
District. The second failure occurred this year at the
Hawthorne (Florida) Volunteer Fire Department. Both
cylinders failed while stored in fire trucks.
Exponent-Failure Analysis Associates (FaAA) in Menlo Park,
California analyzed the cylinders. In its reports, FaAA
concluded that the failures were caused by stress-corrosion
cracking of the fiberglass wraps resulting from exposure to
a strong corrosive agent. Fiberglass composite cylinders are
particularly at risk for stress-corrosion cracking because
the fibers are under constant tension due to the internal
pressure. When the structural integrity of the overwrap is
weakened, a catastrophic failure of a cylinder can occur
that may result in serous injury or death.
Persons responsible for the care of
composite cylinders should take measures to ensure that they
do not come in contact with strong corrosive agents, that
the cylinders are washed only with a mild soap and water
solution, and that all recommendations of the cylinder
manufacturer or distributor in regard to maintenance,
requalification and use are carefully followed.
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