Firefighter Injury Project Investigation Report

FIP Investigation #3

Two Firefighters Injured Due To Exposure to A Refrigerant Gas

Division of Safety Research,
National Institute for Occupational Safety and Health

Firefighter Injury Project (FIP), New Jersey Department of Health (NJDOH)

Two Firefighters Injured Due to Exposure to a Refrigerant Gas, Firefighter Injury Investigation #3


On January 23, 1997, two firefighters were exposed to a refrigerant gas, presumably sulfur dioxide, that was escaping from an old refrigerator. Unaware of the hazard, a firefighter inhaled the gas when he removed his self contained breathing apparatus (SCBA) mask to rest after carrying the refrigerator outside from an apartment. A fire inspector was also exposed to the gas when he entered a room in the apartment that had not been ventilated. Both firefighters experienced adverse health effects after their exposure to the gas.

New Jersey Department of Health (NJDOH) Firefighter Injury Project (FIP) investigators concluded that to prevent similar incidents in the future, the following guidelines should be followed:

  • All uncontrolled chemical releases should be treated as hazardous material incidents.
  • Firefighters exposed to hazardous materials should receive immediate medical evaluations and, if necessary, treatment.


On March 10, 1997, the Firefighter Injury Project (FIP) staff learned about the firefighters' injuries from a newspaper article. On April 3, 1997, the fire department chief was called to ask if the department and injured firefighters would participate in a study of firefighter injuries.

On April 10 and 17, 1997, FIP investigators interviewed the injured firefighters, the incident commander, the training officer and the safety officer. The department's standard operating procedures (SOPs) regarding SCBA and Hazardous Materials Incidents, written Respiratory Protection Program, and training materials were reviewed.

The employer was a paid municipal fire department established in 1863 that served a city of residential and industrialized areas of about three square miles, one square mile of which was parkland. The city's population was about 58,000 in 1996. Department personnel stated that about 3,200 calls were answered each year.

The department's 101 firefighters were divided among two fire stations. The department's command structure included one department chief and four deputy chiefs. Personnel assigned to fire suppression duties worked 24 hours on, and then had 72 hours off. Each shift had a deputy chief assigned to the fire suppression unit.

The department had an extensive training program administered by a full time department training officer. Firefighters were provided with about two hours of drill training on each weekday shift for a total of about 120 hours of training per year. Training for new recruits was provided by the department. New recruits received 268 hours of classroom training and practical exercises that included a New Jersey Department of Community Affairs - approved Firefighter 1 course. Some of the topics covered by the course included SCBA use, hazardous materials response, and firefighting strategies and tactics. The department had a full time safety officer who routinely performed spot checks to determine the firefighters compliance with department SOPs.

The injured firefighter was a 31-year-old male with five years of experience, and the fire inspector was a 32-year-old male with seven years experience as a firefighter.


On January 23, 1997, a man pounded on the fire station door at 10:20 p.m. saying he needed the firefighters help. The incident commander (a deputy chief) drove the man to his apartment as the man explained that he had cut coolant lines in order to remove the compressor from an old refrigerator so it would be lighter to remove from the apartment. When he cut the coolant lines, a refrigerant gas was released, and he inhaled the gas that caused him to have trouble breathing. He realized he needed help. The incident commander, a 38-year veteran of the fire service, entered the third floor attic apartment and recognized the gas to be sulfur dioxide by its odor. Sulfur dioxide was used as a refrigerant prior to 1950.

Meanwhile, two fire department vehicles, with a total of seven firefighters, were on scene shortly after the incident commander entered the building. The firefighters were wearing protective turnout gear and their SCBAs were ready to go on air. As the incident commander left the apartment, he radioed orders to the waiting firefighters to put on the air for their SCBA, ventilate the apartment, and move the refrigerator to the outside. Five firefighters entered the apartment without knowing the kind of hazard with which they were dealing. They opened several windows to ventilate the apartment, and two of the firefighters (including Firefighter #1) carried the refrigerator down the stairs and out of the building. After removing the refrigerator to the outside, Firefighter #1 leaned on the refrigerator to rest and removed his mask. Immediately he began to gag and cough as he inhaled the sulfur dioxide gas. His coughing continued until he returned to the fire station. He stated that he did not know that the gas he inhaled was presumably be sulfur dioxide until the firefighters were en route back to the fire house.

After the refrigerator had been removed, the incident commander ordered a fire inspector to inspect the apartment to determine if it was an illegal apartment. Without wearing his SCBA, the fire inspector entered a room that had not been ventilated and he, too, inhaled the gas. He said he coughed for five to 10 minutes.

The entire incident was over in approximately seventeen minutes. Medical attention was not sought since their coughing subsided and they were not experiencing any other adverse health effects immediately after their exposures. The fire department held an informal critique of the handling of the incident shortly after the injuries became evident.


Within 24 hours of the incident, Firefighter #1's face began to itch. He thought he was having an allergic reaction to something he had eaten, so he went to an emergency room for treatment. Two days later, his face continued to be irritated and a bumpy rash developed on his face which showed the outline of his SCBA mask. Part of his chest also developed a rash apparently because his coat had been opened at the neckline when he was exposed to the gas. The fire inspector said he noticed two days after his exposure that his vision was blurred. Both firefighters reported for their next scheduled tour of duty about 3 ½ days after the incident. After talking to each other, they realized that their symptoms may have been related to their exposure to the sulfur dioxide gas. They both went to an occupational medicine clinic for evaluation and treatment. Firefighter #1 was treated for his skin irritation. He also reported having some breathing difficulty for which he was referred to his own physician. At the time of his interview (approximately 3 months after the exposure), the firefighter reported that the rash had gone away but he still became winded more quickly than he did prior to his exposure to the sulfur dioxide. The fire inspector was also medically evaluated by an occupational health clinic. He said that it took about 1 ½ weeks before his vision was back to normal. At the time of the interview, he mentioned that he was having nose bleeds since his exposure.

The two firefighters were exposed to a refrigerant gas, presumed to be sulfur dioxide. Sulfur dioxide is a very toxic, irritating gas with an odor similar to burning sulfur. Inhaled sulfur dioxide tends to dissolve in the upper airways, combining with moisture to form an acid solution. Exposure to high levels can cause death from severe airway obstruction or pulmonary edema, a buildup of fluid in the lungs that may be delayed hours or days after exposure. Exposure to lower levels can irritate the eyes, nose, and throat, causing burning, dryness, coughing, and chest tightness. Sensitivity varies among people, and short exposures have been found to produce a reversible decrease in lung function. Sulfur dioxide will also react with moisture on the skin to cause irritation and itching. (2 & 3)

Recommendations and Discussion

Recommendation #1:

All uncontrolled chemical releases should be treated as hazardous material incidents.

Discussion: The two injured firefighters were unaware that they were responding to a incident that involved a hazardous material. The New Jersey Public Employees Occupational Safety and Health Standard for Hazardous Waste Operations and Emergency Response, 29 CFR 1910.120 addresses how to respond to emergencies involving potentially hazardous materials. An emergency response plan should be developed and followed. Clear direction should be provided to responding firefighters regarding proper handling procedures that should include the identity of the substance, its location, the associated health and safety hazards, and proper use of appropriate personal protective equipment. Standard turnout gear may not be adequate protection against hazardous materials that may be absorbed through the skin.

Recommendation #2:

Firefighters exposed to hazardous materials should receive immediate medical evaluations and, if necessary, treatment.

Discussion: The two exposed firefighters should have been medically evaluated after their exposure. The incident commander believed that the gas was sulfur dioxide that is a hazardous material. Sulfur dioxide is known to have delayed health effects such as pulmonary edema that may develop 24 to 48 hours after exposure. Immediate medical evaluation and treatment can eliminate or lessen the adverse health effects of exposure to hazardous materials.


  • Hazardous Waste Operations and Emergency Response Standard, 29 CFR 1919.120: NJDOH, PEOSH Program, PO Box 360, Trenton, NJ 08625.
  • Sulfur Dioxide: CHEMINFO, Canadian Centre for Occupational Health and Safety, CD-ROM Issue 96-4 (November, 1996).
  • Sulfur Dioxide: New Jersey Department of Health (NJDOH), Hazardous Substance Fact Sheet; NJDOH, Right to Know Program, PO Box 368, Trenton, NJ 08625.
Last Reviewed: 8/17/2016