NIOSH Warns Workers and Employers of Risk From Aluminum Regulators in High-Pressure Oxygen Systems

Contact: Fred Blosser (202) 260-8519
February 17, 1999

The National Institute for Occupational Safety and Health (NIOSH) is warning fire departments and other emergency care and health care employers and workers about an occupational risk from aluminum attachments or regulators that controls the flow of oxygen from pressurized oxygen tanks or cylinders often used by fire departments and emergency medical services, and in health care settings. A number of factors can contribute to the generation of a fire flash from these aluminum devices during equipment checks or routine use when the valve on the attached cylinder is opened, releasing a flow of oxygen to the regulator.

NIOSH investigated an incident in Florida in which a firefighter suffered first-, second-, and third-degree burns over 36 percent of his body when a flash from an aluminum oxygen regulator released two 4-foot flames during a routine equipment check. NIOSH is disseminating a report based on this investigation that discusses risk factors and suggests precautionary measures for fire departments, emergency medical services, and others who use high-pressure oxygen systems.

The report is posted on NIOSH’s World Wide Web page at www.cdc.gov/niosh/firehome.html. A printed copy will be disseminated soon to 37,000 fire departments and emergency medical services in the U.S. The incident in Florida was one of two cases involving firefighter injury that NIOSH has investigated. A report on the second incident, which occurred in South Carolina, is being finalized.

While comprehensive data are not available, NIOSH is aware of at least 14 incidents involving occupational injuries to 15 firefighters, emergency medical technicians, and health care workers from fire flashes related to aluminum oxygen regulators. For this reason, NIOSH collaborated with the Food and Drug Administration (FDA) on a joint public health advisory that FDA is distributing to an additional 29,000 users of oxygen resuscitation systems, including hospitals, nursing homes, and home health care agencies. The public health advisory is available on FDA’s Web page at www.fda.gov/cdrh/safety.html.

From tests conducted during the Florida investigation, NIOSH determined that a particle of aluminum from the oxygen cylinder entered the oxygen regulator when the cylinder valve was opened during an equipment check. The particle struck a filter component and ignited with the impact during the oxygen flow. In turn, a fire flash was triggered when aluminum in the regulator’s high-pressure section ignited; this is the part of the regulator that high-pressure oxygen enters from the cylinder. A similar hazard can be created from the impact of other types of particles in the oxygen flow, such as dirt or other contaminants.

Using a regulator constructed of bronze, brass, or other materials with comparable heat-resistant properties is a key safety step because these materials, unlike aluminum, are not likely to promote burning from particle ignition during oxygen flow. NIOSH suggested that users consult with the manufacturer to determine if a regulator is made of aluminum.

NIOSH also suggested that:

• In the equipment check, the cylinder’s post valve should be pointed away from the operator and other people, and should be opened slowly and completely once the regulator is attached.
• Workers should be informed of the hazard and trained in safe handling procedures.
• Oxygen cylinders and regulators should be stored and maintained in cool, clean areas.
• Where possible, cylinders should be stored and used in an upright position.
• Any gauge guards or any other components added to the regulator should be obtained from the manufacturer and installed so as not to block regulator vent holes.

“These are prudent, sensible measures for ensuring that needless safety risks are not encountered during critical equipment checks or routine use of high-pressure oxygen systems,” said NIOSH Director Linda Rosenstock, M.D., M.P.H.

For further information on NIOSH research and technical assistance on firefighter safety and other workplace health and safety issues, contact NIOSH at toll-free 1-800-35-NIOSH (1-800-356-4674) or visit NIOSH’s Web page at www.cdc.gov/niosh.