Are Fire Extinguishers Toxic or Poisonous to Inhale?

In the heat of the moment, grabbing a fire extinguisher is instinctual to control a fire. But what happens to your body after you use it?

The question lingers: are fire extinguishers toxic or poisonous? Especially when that white dust clouds the air, is it bad to inhale fire extinguisher powder?

Fear not! We’ll delve into the truth about fire extinguisher contents, separating the facts from smoke and fumes.

Are Fire Extinguishers Toxic?

Fire extinguishers are generally non-toxic to humans but may cause harm if the extinguishing agent is inhaled or ingested.

Are Fire Extinguishers Poisonous?

Fire extinguishers are generally not poisonous but they can cause health problems if used improperly or inhaled excessively. The most common types of fire extinguishers contain dry powders, such as monoammonium phosphate or sodium bicarbonate, that can irritate the skin, eyes, nose, throat, and lungs.

Here are some nuances to consider about the toxicity of fire extinguishers:

  • Chemical Contents: The chemicals used in extinguishers vary by type. Most are non-toxic, but some can cause irritation if inhaled or come into contact with skin.
  • Inhalation: The dust from dry chemical extinguishers can irritate your lungs, especially for people with asthma or respiratory problems. (Also see next point.)
  • Ingestion: While not generally deadly, ingesting any extinguisher agent can cause harm to the body. According to the National Capital Poison Center, deliberate inhalation or ingestion can cause serious symptoms such as pneumonia, seizures, irregular heartbeat, and kidney failure.
Fire extinguisher powder

More On the Effects of Inhaling Fire Extinguisher Powder

Inhaling fire extinguisher powder can have various effects on your health, depending on the type and amount of dust inhaled, the duration and intensity of exposure, and your individual sensitivity.

Some of the possible effects are:

  • Respiratory irritation: The powder can irritate your nose, throat, and lungs, causing coughing, wheezing, shortness of breath, and chest tightness. This can be more severe for people with asthma or other lung conditions.
  • Lung inflammation: The dust can trigger inflammation in the lungs, which can lead to pneumonia, bronchitis, or lung damage. This can be delayed and may not appear until several hours or days after exposure.
  • Allergic reactions: Some people may be allergic or hypersensitive to certain substances in the extinguisher powder, such as monoammonium phosphate, sodium bicarbonate, or halons. This can cause skin rashes, hives, itching, swelling, or anaphylaxis.
  • Systemic toxicity: The extinguisher dust can enter the bloodstream and affect other organs, such as the heart, brain, kidneys, or liver. This can cause symptoms such as dizziness, headache, nausea, vomiting, diarrhea, seizures, cardiac arrhythmias, acidosis, or cardiac arrest. This can be life-threatening and requires immediate medical attention.

If you or someone else has inhaled fire extinguisher powder, you should:

  • Move to a well-ventilated area and breathe fresh air.
  • Rinse your eyes, nose, mouth, and skin with water.
  • Seek medical help if you have any symptoms or concerns.
  • Inform the doctor about the type and amount of powder you were exposed to.

Fire extinguishers can save lives and property, but they should be used with caution and care to prevent inhaling the powder. It is important to use fire extinguishers only in case of emergency and to follow the instructions and safety precautions on the label.

Frequently Asked Questions

Is a water fire extinguisher toxic?

A water fire extinguisher is not toxic, but it uses a high-pressure spray that can cause physical harm if aimed directly at a person. It is suitable for Class A fires involving materials such as wood, paper, and cloth.

Are ABC fire extinguishers toxic?

ABC fire extinguishers are the most common type of fire extinguishers used for Class A, B, and C fires. They contain a dry powder called monoammonium phosphate, which is generally not toxic but can cause irritation to the skin, eyes, nose, throat, and lungs.

If you inhale or ingest the powder, you may experience symptoms such as coughing, wheezing, shortness of breath, dizziness, headache, nausea, or vomiting. These symptoms usually go away with fresh air and water, but you should seek medical attention if they persist or worsen.

Is a dry chemical fire extinguisher toxic?

A dry chemical fire extinguisher is generally not toxic, but it can be irritating to the skin, eyes, nose, throat, and lungs. As a result, dry chemical extinguishers can cause symptoms such as coughing, wheezing, shortness of breath, dizziness, and headache. 

Are CO2 fire extinguisher contents toxic?

A CO2 fire extinguisher is not toxic, but it is a suffocating gas that can reduce the oxygen levels in a small, poorly ventilated area. If inhaled in large amounts, a CO2 extinguisher can cause symptoms such as confusion, loss of consciousness, and even death. It is suitable for Class B and C fires involving flammable liquids and electrical equipment.

Is fire extinguisher foam toxic?

A foam fire extinguisher is usually non-toxic, but it leaves behind chemicals that can irritate the lungs, eyes, and throat, and are possibly carcinogenic in high concentrations and prolonged exposure. It is suitable for Class A and B fires involving solids and liquids.

Is a wet chemical fire extinguisher toxic?

A wet chemical fire extinguisher contains chemicals that can produce toxic fumes when used on a fire. It is important to use it safely and ventilate the area as soon as the fire is controlled to reduce inhalation. It is suitable for Class K fires involving cooking oils and fats.


In conclusion, fire extinguishers are generally non-toxic and safe for home use. However, they can cause health problems if used improperly, ingested, or inhaled excessively to poisonous levels.

While inhaling fire extinguisher discharge can cause irritation, it’s the fire itself that poses the greater risk. When using an extinguisher, prioritize putting out the flames and evacuate the area to minimize exposure to the powder in the air. And, if you do inhale a large amount of dust, seek immediate medical attention.