Fire extinguishers are essential safety devices that are found in homes, businesses, vehicles, and other locations. They are designed to put out small fires quickly before they grow into something much more dangerous. While extremely useful, there are some risks associated with fire extinguishers that owners should be aware of. One question people commonly ask is – can fire extinguishers explode? Let’s take a detailed look at whether fire extinguishers can explode, the causes, and steps to take to prevent explosions.
How Fire Extinguishers Work
Before examining if and how fire extinguishers can explode, it’s helpful to understand how they work. There are several different types of fire extinguishers, but they all operate on the same basic principle.
Fire extinguishers contain a compressed gas propellant, typically nitrogen or carbon dioxide. When the trigger handle is pressed, the pressurized gas pushes a directed stream of extinguishing agent out of the nozzle towards the fire. Different extinguishers contain different types of extinguishing agents depending on the type of fire they are designed to fight. Common agents include water, foam, dry chemical powder, wet chemical, and clean agents.
The extinguishing agent smothers and disrupts the fire triangle (heat, fuel, oxygen) to stop the combustion process. The pressurized gas propellant provides the pressure and force needed to shoot the extinguishing agent out up to 30 feet or more.
Can Fire Extinguishers Explode?
The simple answer is yes, fire extinguishers can explode under certain unlikely but possible conditions:
- Overpressurization – If pressure builds up to dangerous levels inside a damaged or malfunctioning extinguisher tank, an explosion can occur. Overheated conditions can cause excessive pressure buildup.
- Combustion of Extinguishing Agents – Some fire extinguishing agents like dry chemical powder can be explosive in high concentrations and certain conditions. Enclosed spaces increase explosion risk.
- Ruptured Tank – If the pressurized cylinder tank is damaged, punctured, corroded, or experiences an equipment failure, the sudden release of pressure can cause an explosive rupture.
- Heat Exposure – Exposing fire extinguishers to extreme heat or even direct flame can potentially cause the pressurized tank to rupture and explode.
So while rare, it is possible for a fire extinguisher tank to explode if the right conditions align. It requires some type of triggering event like damage, overpressurization, or heat exposure to cause a catastrophic failure.
What Factors Can Lead to Explosions?
There are a few key factors that can increase the likelihood of a fire extinguisher explosion:
- Damage – Dents, cracks, corrosion, or punctures in the pressurized tank can weaken its structural integrity and make explosions more likely if exposed to internal pressure or heat.
- Overcharging – Overfilling the tank with pressure above the safe design limits makes explosions more likely. This may occur with improper maintenance.
- High Temperatures – Exposure to temperatures exceeding 120°F-140°F can cause excessive internal pressure buildup and possible tank rupture in fire extinguishers.
- Improper Handling – Dropping, throwing, or severely jostling fire extinguishers can damage them and lead to potential explosions.
- Age – Very old fire extinguishers that have corroded or weakened over many years pose a greater explosion risk.
- Wrong Extinguisher for the Fire Type – Using the wrong type of extinguishing agent for a given fire can feed the flames and lead to overheating of the extinguisher.
By being aware of these factors and taking preventative measures, the already low risks can be further minimized.
What are the Dangers of Fire Extinguisher Explosions?
While rare, fire extinguisher explosions can be dangerous in a few key ways:
- Propulsion of Tank Shrapnel – The force of the blast can send pieces of metal shrapnel flying at high speeds, which may lead to puncture wounds or other injuries. Staying clear of the extinguisher is critical.
- Blast Injuries – The overpressure wave released by the explosion can cause ear drum rupture or even organ damage at close range. Fragments ejected at high speed amplify these hazards.
- Thermal Burns – Contents that are flammable and on fire may spread flames and cause burn injuries following an explosion. This is mostly a concern with cart-style propane tanks.
- Smoke Inhalation – Toxic smoke released from combustion of chemical agents may pose a health hazard and require evacuation.
- Slips/Falls – Intense noise, debris, and gasses can startle people, potentially leading to injuries from falls and accidents in the vicinity.
While explosion hazards exist, they can be minimized with proper handling, maintenance, and placement of fire extinguishers. The benefits outweigh the risks when simple precautions are followed.
Steps to Prevent Fire Extinguisher Explosions
Here are some key measures you can take to avoid fire extinguisher explosions:
- Inspect Monthly – Check for any signs of damage, corrosion, leaks or blockages. Weigh cartridges annually to check for loss of agent/pressure.
- Proper Storage Conditions – Do not expose extinguishers to temperatures exceeding 120°F or freezing temperatures. Store in clean, dry areas.
- Mount Securely – Install wall hooks and brackets to keep extinguishers secured and avoid dropping or falling over.
- Replace Old Extinguishers – Replace any units over 12 years old or beyond their expiry date. Older units pose greater explosion risk.
- Train Personnel – Educate staff on proper operation, handling, and hazards associated with extinguishers. Stress not fighting large fires.
- Have Professionals Service Annually – Maintenance helps ensure pressure systems stay in certification and reduce explosion risk.
- Locate Away From Heat Sources – Avoid placing extinguishers too close to heat emitters like ovens and heaters where possible.
- Use Proper Extinguisher for Fire Type – Using the wrong agent on a fire can lead to splashing, excessive heat, and potential explosion hazard.
With training, maintenance, and smart placement, the average person can take proactive measures to avoid fire extinguisher explosions. But it’s also critical to evacuate and call professionals if a major fire breaks out rather than tempting fate against the blaze on your own.
Fire Extinguisher Explosion Case Studies
There are some notable real world examples of fire extinguisher explosions in recent history:
- New York Coffee Shop (2016) – A small CO2 extinguisher exploded in a Brooklyn coffee shop, sending a female employee to the hospital requiring stitches. The tank shot 30 feet striking her leg.
- London Nightclub (2013) – A dry chemical powder extinguisher exploded at a crowded London nightclub during a fire, injuring 14 people from burns and smoke inhalation requiring hospital visits.
- Boston Hotel (2012) – A fire extinguisher explosion blew out windows on lower floors at the luxury Taj Boston hotel, spraying nearby pedestrians with chemical powder but causing no serious injuries.
- Kansas Chemical Plant (2007) – Overheated ammonium nitrate at an agricultural chemical plant caused the explosion of a large 300-pound dry chemical wheeled extinguisher, necessitating a plant evacuation but no major injuries.
- Texas School (2005) – A student-set fire triggered the explosion of a dry chemical extinguisher, blowing out windows and sending 10 students and staff to the hospital with minor injuries from chemical exposure.
These examples underscore the importance of proper handling, placement, maintenance, and training for fire extinguisher safety. While explosions do occasionally occur, preparing people and equipment appropriately can greatly reduce risks.
Key Takeaways on Fire Extinguisher Explosions
To wrap up, here are some key facts to remember:
- Fire extinguishers can in fact explode in rare cases of damage, overpressurization or heat exposure.
- Key risk factors include damage, overcharging, high temps, improper handling, age, and using the wrong extinguisher.
- Dangers include shrapnel, blasts, burns, inhalation, and slips/falls.
- Take preventative measures like inspection, maintenance, proper storage, mounting, training, and fire-matching.
- Case studies provide real examples, though explosions are still highly uncommon events.
- When major fires occur, evacuate and call professionals rather than attempting to fight it yourself.
While the thought of an exploding fire extinguisher may seem alarming, the actual risks are extremely low, especially when basic safety steps are followed. These inexpensive devices save lives and property on a daily basis when used as intended. With proper handling and maintenance, fire extinguishers remain very safe and effective tools for protecting against small fires in their early stages.