Anatomy of a Dryer Fire


What does the anatomy of a dryer fire look like? It’s typical to think of a dryer fire as the result of an electrical problem, but did you know that it’s more likely to catch because of lint buildup?


Dryer fires usually start beneath the dryer when the motor overheats. Overheating is caused by a build-up of lint in the duct that increases the drying time and blocks the flow of air due to a clogged dryer vent.

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In most cases, clothes dryer fires can be prevented. “Failure to clean” is the number one factor contributing to clothes dryer fires, followed by mechanical and electrical failure.


The anatomy of a dryer fire is made up of the following three elements. When combined, you could find yourself in the unfortunate situation of a dryer on fire.



Anatomy of a Dryer Fire - Element #1: Oxidizing Agent (Oxygen in the Air)

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Fire occurs when combustible fuel in the presence of oxygen at extremely high temperatures becomes gas. Flames are the visual indicator of the heated gas. It’s important to know that fire can also occur from lower-temperature sources.


So where does the heating source come from hours after the dryer is turned off? To better understand the process we have to understand what is meant by oxidation.


In a general sense, oxidation refers to the combination of a material with atmospheric oxygen, which results in the release of heat. As the temperature increases, so does the rate (or speed) of oxidation.


Not all oxidation reactions result in the accumulation of heat. In some cases, oxidation which is very slow at the beginning and dissipates rapidly, and the temperature does not change measurably.


A classic example of slow oxidation is the combination of iron with atmospheric oxygen, resulting in the formation of rust. Unlike the oxidation of lint, iron is a good conductor of heat and so the heat is quickly dissipated.



Anatomy of a Dryer Fire - Element #2: Combustible Materials (Lint from the Clothes)

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Materials that can catch fire and burn are classified as either flammable or combustible, depending on the temperature at which they ignite.


One good example of a dryer fire culprit is the lint that gets into the machine’s heating element, sparking and fueling a fire. Lint is highly flammable, and it’s everywhere. It naturally accumulates in your dryer and dryer exhaust system.


This buildup makes the dryer work harder for each load and the lint can work its way into the heating element, which is bad news.


The most common cause of dryer fires is a failure to do a thorough cleaning. Because a lint trap is not a foolproof method for catching all the fuzzy stuff from clothes, lint can gradually build up and catch fire in the heating element or exhaust duct.


Benefits of keeping your dryer vent cleaned regularly:


  • Allows your dryer to operate more efficiently, using less energy and saving you money

  • Protects your dryer from excess wear and premature death

  • Helps clothes dry faster — a time saver for busy families

  • Reduces excess household dust and humidity

  • Helps preserve clothing, as the life of many fabrics is damaged by excessive high heat


Because of the way homes are built today, dryer exhaust vent inspections are more important than they’ve ever been. Previously, dryers were located next to outside walls, which made the dryer venting system easy to keep clean.


Nowadays, dryer ducts are more difficult to access. There is additional length, and the greater distance means, among other things, that birds and animals can take up residence there.


Have you got a long duct run? This can accelerate the buildup of lint. If you have access to the exhaust system, venting products like the airflow-efficient Dryer-Ell can be used to replace all the restrictive elbows, making it easier to get the lint out. Less lint is good.



Anatomy of a Dryer Fire - Element #3: Ignition Source (Heat from the Dryer)

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The dryer’s heating element can reach temperatures of 550°F. Forensic testing shows that cotton and wool clothing will ignite at temperatures of 250°F. Therefore, a dryer fire is virtually imminent if lint from clothing comes in contact with the dryer heating element.


Spontaneous combustion fires will not typically occur while the dryer is running. The tumbling action of the dryer and the forced airflow out of the dryer vent prevent the buildup of heat in the clothing. Spontaneous combustion fires normally happen when there’s an interruption in the drying cycle, before the dryer has completed the “cool down” portion of the drying cycle.


Remember: Don’t interrupt or stop your clothes dryer and always let it complete the cool-down process. Following this rule may just prevent dryer fires from occurring in your home or business.


The most proactive thing you can do to prevent the risk of a dryer fire is to ensure you’re vigilant enough to know how to prevent them in the first place.



Warning Signs of an Imminent Fire


The dryer is still producing airflow but not heat. It takes longer and longer to dry clothes, especially towels and jeans or thick articles of clothing.


Clothes are damp or hotter than usual at the end of the cycle.


The outdoor flapper on the vent hood doesn't open when the dryer is on. 


Airflow in the vent seems low.



Tips to Prevent Dryer Fires


Clean out the lint. Clean out the lint filter every time you use the dryer.


Clear out the vent pipe to reduce the chance of fire and to maintain the efficiency of the dryer.


Install with care. Be sure to follow the manufacturer’s instructions when installing the vent pipe.


Clear out combustibles. Move any flammables like cleaning supplies far away from your dryer.


Opt for a solid metal dryer duct.


Read tags. If the care label reads tumble dry low, don’t turn the dryer up to high.


Don’t dry and dash. Turn off your dryer if you need to step out during the laundry cycle.



Worried about a Possible Dryer Fire?  Call Us Today


The good news is dryer fires are easy to prevent. Cleaning the lint screen after every load will make a big difference in dryer performance and energy savings.


However, very few people realize the danger of clothes dryer fires. Even when you’ve taken all the right steps to prevent a dryer fire, accidents can happen.


Don’t wait until the worst happens! Southern California Dryer Vent Cleaning specializes in nothing but dryer cleaning and your safety is our main goal.


We have the right equipment and are expertly trained to diagnose and solve all types of possible dryer fire problems. We’ll provide efficient solutions to whatever dryer cleaning problem you are facing.


Call us today at (951) 290-3105 or request an appointment online to address all your dryer related concerns.


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Anatomy of a Dryer Fire