When exposed to high temperatures and direct sunlight,
propylene cylinders can spontaneously vent through their
relief devices, in turn releasing propylene, which when
ignited, can heat surrounding cylinders and cause them to vent, creating
a domino effect that spreads the fire. This is what occurred on June 24,
2005 at Praxair’s gas filling and distribution facility in St. Louis,
Missouri. A small fire from one propylene cylinder spread to others and
then to propane and acetylene cylinders. Exploding cylinders flew up to
800 feet, damaged property, and started fires in the community. The fire
could not be extinguished until most of the flammable gas cylinders were
expended.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) issues
this Safety Bulletin to focus attention on the propylene gas cylinder
hazards that contributed to the fire and explosions at the Praxair facility
and specific actions that propylene gas vendors can take to prevent
similar incidents, which include: