Pool Chemical Fires: The Dos and Don'ts of Using a Fire Extinguisher
Pool chemical fires are different
In Las Vegas, almost every apartment complex, hotel, HOA, and backyard has a pool. That means a lot of pool chemicals sitting in sheds and storage rooms, often in extreme heat.
Most people think any fire extinguisher will work on any fire. With pool chemicals, that is not true. The wrong extinguisher can fail completely, or even make the fire worse and release toxic gas.
This guide explains why pool chemical fires are different and what to do, and not do, if one starts.
Why pool chemicals burn differently
Most pool chlorine products are oxidizers. An oxidizer does not burn by itself, but it gives off oxygen that makes other things burn hotter and faster.
That matters because most fire extinguishers work by cutting off oxygen. An oxidizer brings its own oxygen, so smothering the fire does not work. The EPA label for one calcium hypochlorite product says that smothering with a wet blanket, CO2, or a dry chemical extinguisher is ineffective.
Common pool chemicals that act as oxidizers include:
Calcium hypochlorite ("cal hypo"), sold as granules or tablets for shock treatment
Trichlor and dichlor, the chlorine tablets and granules used in floaters and feeders
Liquid chlorine (sodium hypochlorite)
Pool acids, such as muriatic acid, are not oxidizers. But if acid mixes with chlorine, it releases toxic chlorine gas. That is why these products must never be stored together.
The don'ts
Don't use an ABC dry chemical extinguisher. This is the most common extinguisher in homes and businesses. Its powder is usually monoammonium phosphate. Calcium hypochlorite safety data sheets warn against using dry extinguishers that contain ammonium compounds. Mixing the two can cause a violent reaction and a fire of great intensity.
Don't count on CO2 or foam. The Emergency Response Guidebook says not to use dry chemicals or foam on oxidizer fires. CO2 may give only limited control, because the chemical keeps supplying its own oxygen.
Don't use a small amount of water. A little water on calcium hypochlorite can make it react violently, giving off heat, toxic gas, and spatter. If water is used, it must be a large amount.
Don't try to fight a large fire. A fire involving a storage room or a pile of pool chemicals is a job for the fire department.
Don't breathe the smoke. Burning pool chemicals give off chlorine and other toxic gases. Stay upwind and stay back.
The dos
Do get everyone out and call 911. Tell the dispatcher that pool chemicals are involved. Firefighters need to know before they arrive.
Do use lots of water, and only if it is safe. Safety data sheets for calcium hypochlorite call for water only, in flooding amounts. For a small fire that has just started, a garden hose or a water-type extinguisher from a safe distance is the right tool. Never add just a splash.
Do stay upwind and keep your distance. Chlorine gas is heavy and stays low to the ground. Keep people and pets away.
Do cool nearby containers from a distance. If it is safe, spray water on nearby chemical containers to keep them from heating up and joining the fire.
Do keep the right extinguisher near your chemical storage. Ask a licensed fire protection company to recommend an extinguisher for your pool equipment area. Label it so no one grabs the ABC unit by mistake.
Do keep the safety data sheet (SDS) handy. The SDS for each chemical lists the right way to fight a fire. Keep copies where staff and firefighters can find them.
Preventing pool chemical fires in Las Vegas heat
The best way to handle a pool chemical fire is to never have one. Heat is a big risk here. Some calcium hypochlorite safety data sheets say not to store the product where the average daily temperature is above 95°F. Above that, it can break down, release chlorine gas, and get hot enough to ignite nearby materials. Las Vegas summers are well above that.
Keep chemicals cool and shaded. Never store them in direct sun, a hot car, or an unvented shed.
Keep them dry. Close lids tightly. A small amount of water or humidity can start a reaction.
Store chemicals apart. Keep chlorine away from acids, other pool chemicals, fuels, fertilizer, oils, and anything that burns.
Never mix products. Use a clean, dry scoop for each chemical. Never put one product into another product's container.
Keep them in the original container, with the label on.
Keep the storage area clean. Sweep up spills right away with a clean, dry broom.
Keep your extinguisher out of the chemical room. Store ABC extinguishers away from pool chemicals so powder never mixes with them.
Quick checklist
Pool chemicals stored cool, dry, shaded, and in original containers
Chlorine kept away from acids, fuels, and other chemicals
No ABC extinguisher stored inside the chemical room
The right extinguisher nearby and clearly labeled
Safety data sheets posted where staff can find them
Staff know to get out and call 911 first
Not sure which extinguisher you need? Call Ace Fire Systems
Ace Fire Systems has helped Southern Nevada pools, hotels, apartment communities, and HOAs stay fire safe since 1993. We are licensed by the Nevada State Fire Marshal. We can look at your pool equipment area, recommend the right extinguishers, and keep them inspected.
Call us at 702-384-2932 or visit AceFireNV.com.
