Author(s): Ben Klaene, Russ Sanders. Published on November 1, 2011.

Lives in the Balance
Risk vs. benefit in the determination of an imminent life hazard

NFPA Journal®,  November/December 2011

NFPA 1500, Fire Department Occupational Safety and Health Program, requires that a minimum of four firefighters be on the scene before entering the hazard area at a working structure fire. Two of these firefighters must be outside the hazard area ready to rescue or help the team entering the area. This is commonly referred to as the two-in/two-out rule.



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However, an exception in Section 8.5.17 of NFPA 1500 states that “initial attack operations shall be organized to ensure that if, on arrival at the emergency scene, initial attack personnel find an imminent life-threatening situation where immediate action could prevent the loss of life or serious injury, such action shall be permitted with less than four personnel...” How does the officer on this first-arriving company determine if there is an imminent life hazard where actions could prevent the loss of life or serious injury?

Time and occupancy factors provide clues as to the potential life hazard. Late at night, there is a high probability that the occupants of a single-family residence are at home, although there might be a chance that the house is unoccupied. Conversely, an office building or school is not likely to be occupied late at night, although security, maintenance, or janitorial employees could be working. Even in a vacant building, there is a possibility that the fire was started by children, vandals, or vagrants who are still inside the building.

In most cases, the first-arriving officer will not know with 100 percent certainty that the fire building is unoccupied. Reports from occupants who escaped from the building can improve firefighters’ confidence in the building’s occupied or unoccupied status, and visual observations often verify that occupants remain in the building.

In a risk-versus-benefit analysis, the risk to firefighters is weighed against the benefit of saving lives and property. The probability of occupancy is compared to the risk to firefighters, along with other factors, to determine if an offensive attack is warranted. The risk is greater when fewer than four firefighters are at the scene, so the degree of confidence regarding savable victims must also be higher. A fast-moving fire in a large compartment or a fire involving several compartments presents an increased risk to firefighters and a decreased chance of survival for the occupants, compared to a fire confined to a small area that can be easily extinguished using a single 1¾-inch attack line.

Think of the risk-versus-benefit analysis as a balance scale. Where there is a low probability of saving a life, the weight on the benefit side of the scale is low. This low benefit is matched with a low risk on the part of firefighters. If there is a very high probability that savable victims are still endangered in the fire area, the acceptable risk to firefighters is higher, but firefighters should never unnecessarily be put at extreme risk.

A risk-versus-benefit analysis is necessary to apply Section 8.3.2 of NFPA 1500, which states that the concept of risk management should be used based on the following principles: activities that present a significant risk to firefighters’ safety should be limited to situations in which there is a potential to save lives; activities that are routinely used to protect property should be recognized as inherent risks to firefighters’ safety, and actions should be taken to reduce or avoid these risks; no risk to firefighters’ safety is acceptable when there is no possibility to save lives or property; and, in situations where the risk to fire department members is excessive, activities should be limited to defensive operations.

This column is adapted from the author's book StructuralFireFighting, available online or (800) 344-3555.