Safety & Survival: Risk Assessment of Fireground Hazards

The fire environment is full of dangers. The surrounding atmosphere of a fire scene may include gas explosion, collapse, falls, falling objects, rollover, flameover, flashover, backdrafts, fire, smoke, heat, disorientation or electrocution. Perilous surroundings and a deadly uncontrolled environment are the firefighter’s workplace.

Every firefighter at the scene of a fire is exposed to those 13 common risks. These recurring dangers are inherent hazards of firefighting. They threaten every firefighter performing every fire task at every location near any fire. Any of these deadly hazards can kill or injure a firefighter operating inside or outside a building fire.

The following are some facts about these 13 deadly fireground hazards.

Gas explosion – Happens instantly, with no warning. Explosions are often caused by leaking natural gas or propane or a boiling liquid expanding vapor (the resulting explosion is called a BLEVE). And after an explosion, shock waves result in flying glass and shrapnel, a structure collapse and fire spread.

Collapse – Collapses of burning buildings usually kill more than one firefighter. Most firefighters die from floor, roof, wall and ceiling collapses, in that order. When an entire building collapses, as happened on 9/11, it is called a global collapse.

Falls – Occur most often at ground level. Firefighters slip on ice or trip over objects at night rushing to get into position to fight a fire. Slips and tripping are leading causes of injury in the fire service. Tunnel vision due to stress block out tripping hazards. Most falls occur at ground level, followed by stairs and ladders. Falls from heights, such as from ladders, fire escapes and roofs are the most deadly.

Falling objects – These kill and injure firefighters working around the perimeter of a burning building. Building pieces, tools, glass and objects that fall or are thrown from heights around the perimeter of a burning building are all classified as falling objects. To protect against falling objects, go inside the building or stay away from the collapse zone around the perimeter.

Rollover – Happens before flashover. Rollover is described as flashes of flame mixed with smoke coming out of a door or window of a fire area. Flameover occurs in stairways, hallways and lobbies.

Flameover – Described as rapid flame spreading over the surfaces of walls, ceilings and/or floors of a burning building. A flameover fire can be caused by a buildup of many coats of oil-based paints on walls, ceilings and stairs.

Flashover – A term used to describe a smoke-filled room suddenly bursting into flame. Flashovers occur more frequently than backdrafts. The trigger for a flashover is heat. Heat buildup causes a flashover. Flashovers occur during the growth stage of a fire. The temperature in a room that flashes over can reach 1,000 degrees Fahrenheit.

Backdraft – A smoke explosion that is a rare event. The trigger for a backdraft explosion is air. A backdraft is an explosion that may occur when searching firefighters introduce fresh air to an atmosphere of combustible smoke and heat.

Fire – Fire should not be passed by searching firefighters. Fire can cut off escape and trap and kill firefighters who pass it and or search above it during firefighting.

Smoke – Smoke kills most people trapped in fire. Smoke is solid particles of soot produced by combustion. Smoke obscures vision and causes firefighters to become disoriented and trapped in fire.

Heat – The heat of a fire causes stress-related injuries, such as heart attack, heat stroke, heat exhaustion and hyperthermia. Firefighter protective clothing cannot stop heat. Rotating firefighters to a rehabilitation unit for temporary rest periods during a fire protects them from heat exhaustion.

Disorientation – Defined as the loss of direction due to the loss of vision. Disorientation during firefighting can result from darkness, smoke and a structure’s maze-like partitions or room configurations. Firefighters who lose a sense of direction searching in smoke are caught and trapped by fire.

Electric shock – A fireground killer inside or outside a burning building. Firefighters using metal ladders and hose streams near overhead wires are in danger of electrocution. All electric utilities should be shut down before overhauling begins.

Some fireground hazards are more dangerous than others; some occur more frequently than others. A risk assessment of the degree of danger and frequency of occurrence will help us evaluate our work hazards. Firefighters must know which hazards are more dangerous and which are more likely to occur.

The following are two lists of fireground hazards. The first list ranks the degree of danger of each hazard and the second list ranks hazards by their frequency of occurrence.

  • Degree of danger – Estimated degree of danger during structural firefighting in urban area, ranked from most dangerous (number one) to least dangerous (number 13). Variables to be considered include the speed of occurrence, area of hazard, warning signs before event, frequency of occurrence, protective equipment of firefighters and defensive-measure training:

Gas explosion (shock waves, shrapnel, fire, collapse)

Electrocution (high voltage, locked muscles)

Collapse (global failure; entire building is danger area)

Fire (firefighters caught and trapped in areas beyond and above flames)

Heat stress (cause of heart attack)

Flashover (1,000-degree Fahrenheit heat; the point of no return)

Disorientation (precursor to fire or smoke as cause of death)

Smoke inhalation (carbon monoxide, mask protection)

Falls (depends on location; ground level, stairs, ladders)

Falling objects (perimeter of building is danger area)

Backdraft explosion (not as common as gas, arson liquid, BLEVE)

Rollover (warning sign of flashover, stay low, withdraw, warn those above)

Flameover (danger areas include stairs, halls and lobbies)

Frequency of danger – The estimated frequency of occurrence of fire dangers during structural firefighting in an urban area, ranked from most often (number one) to least often (number 13):


Heat stress

Falling objects

Smoke inhalation





Electric shock


Gas explosion



Some risks present a high degree of danger, but have a low frequency of occurrence. Other risks present less danger but high frequency of occurrence. However, all of them are deadly.