June 12, 1998, began like every other day for Broward County, FL, Firefighter Roy Williams Jr. Along with other firefighters, Williams was inspecting the trucks and equipment at the start of their shift. But this day would be different for Williams.
While checking the oxygen cylinder, a flash fire occurred, causing Williams to be burned. Another firefighter inspecting equipment on the opposite side of the truck used a water hose to put out the fire. As a result of the flash fire, Williams suffered first- and second-degree burns over 39% of his upper body.
What happened to Williams has not been the only report of a flash fire or explosion occurring after someone turned on an oxygen cylinder. In the last five years, there have been a reported 16 cases of oxygen regulators exploding or burning, injuring or burning 11 people seriously. Most were rescue personnel, but some patients have also been injured.
As a result of the flash fires, the U.S. Food and Drug Administration (FDA) and the National Institute for Occupational Safety and Health (NIOSH) have issued a public health advisory with respect to a potential for fire or explosion with oxygen regulators. The FDA and NIOSH believe the aluminum in oxygen regulators is a major factor in both the ignition and severity of the fires. Most of the reports received by the FDA were for the Model L270 series of aluminum regulators manufactured by Life Support Products Inc. and Allied Healthcare Products Inc. of St. Louis. Allied Healthcare Products makes 60% of the oxygen regulators sold.
Earlier public health advisories were issued by the FDA in May and August 1998. Those two advisories warned of possible explosions or fires involving Life Support Products brand Model L270 oxygen regulators. There were concerns that the regulators were possibly becoming contaminated with hydrocarbons, which in the presence of high-pressure oxygen could undergo spontaneous combustion. At the time, Allied Healthcare offered to retrofit the regulators in question with a sintered bronze inlet filter to reduce the possibility of introducing hydrocarbon contamination. This time, however, the public health advisory from the FDA and NIOSH issued on Feb. 4, 1999, was for ALL aluminum oxygen regulators - not just those sold by Allied Healthcare. The advisory recommends ultimately that all aluminum regulators be replaced with brass regulators. In the interim, the advisory recommends the internal components of aluminum regulators be replaced with brass components.
What is believed to be at the core of the problem is that aluminum and its alloys are more likely to ignite than brass. In standard tests, aluminum can burn vigorously at pressures as low as 25 psi, while brass does not burn at pressures below 10,000 psi. The FDA reports it is working with the manufacturers of oxygen regulators to improve safety and curtail the use of aluminum exposed to high pressure oxygen in regulators.
Virtually every fire department in the country uses oxygen regulators when treating patients who need oxygen. There are an estimated 200,000 oxygen regulators in use. This problem, therefore, puts anybody using an oxygen regulator at risk. What can you do to minimize this risk?
First, if you now use high-pressure oxygen regulators which contain any aluminum exposed to high-pressure oxygen, replace them with regulators made of brass. If you are not sure what your regulators are made of, consult the manufacturer. Undoubtedly, the manufacturer will send you a new regulator or a retrofit kit in the interim.
Second, since oxygen does not burn, but supports combustion, there should be no smoking around oxygen. Material which would not normally burn in normal air may burn in high-pressure oxygen - such as the aluminum in oxygen regulators. Do not let post valves, regulators, gauges and fittings come into contact with oils, greases, organic lubricants, rubber or any other combustible material. In essence, the oxygen tank, cylinder valve and regulator should be free of all contaminants.
The cylinder valve should be opened slowly whenever the unit is used to minimize heat of rapid compression in the regulator. Additionally, any fire department that refills its own oxygen cylinders from a cascade system should take extra care to avoid the introduction of contaminants during the filling process.
Any department that experiences problems with oxygen regulators should report the incident to the FDA. The Safe Medical Devices Act of 1990 mandates hospitals and other users to report deaths, serious illnesses and injuries associated with the use of any medical device. The goal should be that every member of every fire department after a call or tour of duty return home safely in the same physical and mental condition by which they went to serve their communities that day.
Gary Ludwig, MS, EMT-P, a Firehouse® contributing editor, is the chief paramedic for the St. Louis Fire Department and is currently serving his fourth term as an elected member of the EMS executive board for the International Association of Fire Chiefs. He was awarded Missouri's EMS Administrator of the Year for 1998.