Paint is a common substance used in many households and industrial workplaces. Many of us have spare cans or old tins piled up in our sheds and beneath our stairs.
But is this innocuous (and very useful) substance actually a fire hazard that could be putting us and our homes at risk? Well, in short, yes, it could. But don’t panic, there are many different types of paint and some are more flammable than others.
And, when the correct storage and safety measures are followed, even flammable paints can be controlled and safe to use. Read on for a look at what makes certain types of paint flammable, and what precautions and practices you can take to ensure you are using them safely.
Overall, oil based, solvent based and alcohol/spirit based paints are flammable.
If you are an artist who likes to paint with oil paints, someone who is decorating the exterior of your house, or someone who uses spray paints, then you should be aware of the potential fire risks your paints pose and should be sure to follow proper storage and usage guidance.
By contrast, paints that are water-based are not considered to be flammable. Watercolors, acrylics, emulsions and most other interior paints are perfectly safe to use and store in and around your home.
Most paints lose their flammability once dry because the flammable vapors dissipate and evaporate. However, some paints can become combustible once dry and will still therefore catch on fire if they are exposed to extreme heat.
What Is The Difference Between Flammable And Combustible?
To understand which paints are flammable, which are combustible, and which are neither, we must first understand the difference between these two terms.
In spoken English, flammable and combustible tend to be interchangeable words, however they have a slightly different meaning in scientific terms.
A combustible material is something that can (has the capacity to) burn in air. Many materials are technically combustible if they are exposed to air that is hot enough. The dictionary definition of ‘flammable’ is when a substance catches on fire ‘easily’.
A flammable material is a combustible material that will ignite in ‘ambient temperatures’. This means, for a material to be classified as flammable, it has to set on fire easily when exposed to a flame or fire.
What Is A Flashpoint?
Now that we understand the difference between combustible and flammable materials, let’s look at what is meant by ‘flashpoint’ so that we can understand why some paints fall into the flammable category and others do not.
A flashpoint is the temperature at which a material / substance will ignite. This flashpoint is what we use to decide whether a substance is flammable or not. A good way to understand it is to remember that ‘the lower the flashpoint, the more flammable the substance’.
This is because a low flashpoint indicates that something will set on fire at a relatively low temperature, whereas a high flashpoint indicates that you would have to expose that substance to a very high temperature in order for it to set on fire.
What Classifies Something As Flammable?
The official standards for Occupational Safety and Health Administration (OSHA) are set by the US Department of Labor. These guys decide what classifies a substance as flammable or non-flammable, and these classifications apply to all general-use paints.
The rules and regulations surrounding industrial settings differ slightly, however we are concentrating on general use purposes and standards in this article.
According to the OSHA, a flammable liquid is any liquid that has a flashpoint of 199.4 degrees Fahrenheit or below. This is the equivalent of 93 degrees celsius. Any liquid paints, be they in tins, tubes, tubs or cans, with a flashpoint that falls into this category is ‘flammable’.
Of course, the overall flammability of different paints also takes into consideration what other substances are mixed with the flammable substance, and what the ratio between these substances is.
If a flammable liquid is diluted and the paint contains a very low percentage of it, then it may not be classified as flammable. Different types of paint fall into different categories due to these variables.
Types Of Flammable Paints
If a paint has a flammable base substance, like oil, alcohol or solvents, then it will generally be flammable. The main types of flammable paint include:
Spray paint is highly flammable due to the gas propellants that it contains; these are usually propane or butane and are extremely flammable in nature.
Fumes that escape from old cans, damaged cans, or cans that are not closed properly, can ignite and lead to terrible consequences. What is more, due to the pressure inside the aerosol can, spray paints can sometimes flashback.
This is when escaped fumes catch alight and draw heat back inside the pressurized canister (almost like an invisible fuse string). Once the liquid inside the canister heats it will potentially explode like a grenade, and the metal canister becomes shrapnel.
Once spray paint has been applied to a surface and dries however, it is no longer flammable. The gas propellants evaporate and the paint cures and becomes safe.
If you have spray paints at home or at work, make sure you keep them away from heat and flames and that you store them away from other flammable materials. You should also dispose of them responsibly once they are empty, damaged or old.
Solvent Based Paint
Solvent based paint is flammable due to the solvents it contains. For this reason, solvent based paint should be stored in a cool place, away from other flammable materials and never used near heat or flames.
Once dried, the flammable properties in the solvents evaporate and solvent based paint is no longer flammable.
Oil paints are highly flammable, which makes sense when you think of how oil is used to fuel heaters and fires. The solvents in oil paint evaporate and cure as it dries, therefore making it no longer flammable once dry.
However, oil paint is combustible once dry which is why oil paintings will burn to ash in a house fire. If you are a keen oil painter, be sure to store your paints safely, no where near heat or flames, and to always close and seal the tubes properly after use.
Oil-based Enamel Paint
Some types of enamel paint are oil based and are therefore flammable due to the solvents in the oil. However, there are excellent water based enamel paints available these days that are safer to use, store and create the same finish.
Exterior House Paint
Many types of exterior house paint tend to be oil based and are therefore flammable.
They are oil based to make them weather resistant and resilient, however you should always be mindful when storing large amounts of these paints at home or on a building site as they do pose a potential fire risk.
You should use an external paint store when possible, and make sure that the paint store is a good distance from the house. You should also make sure that the paint store is far from heat and flame sources and that children cannot get into it.
Oil Based Epoxy Paint
Due to the solvents used in oil based epoxy paint, it is categorized as a flammable substance. However, you can get water based epoxy paint that is safer to use and will not catch fire.
It is generally used to paint garage floors and other hardy surfaces and if you have a large amount of oil based paint in your home then you should take extra precautions. Once dried the flammable properties dissipate, however the resin of dried epoxy paint is combustible.
Types Of Non-Flammable Paint
As a general rule, paints that are ‘water-based’ are non-flammable. This is because water is not a flammable liquid and it is actually used to extinguish flames rather than to fuel them.
If a paint has a high enough water content then it too can actually be used as a flame retardant. However, there are always exceptions to this rule, and some water-based paints have the capacity to dry-out and become combustible.
If you invest in flame resistant paint they contain certain chemicals that actively prevent the spread of flames around your house.
Types of non-flammable paint include:
Acrylic paint is water based and is therefore non flammable and safe to use and store in your home. However, when acrylic paint dries it changes from a liquid to a solid, known as plastic polymer.
This substance is flammable so you should be careful not to hang acrylic paintings near open fires, and not to place ornaments painted with acrylics near fires either.
Water colors are one of the most safe types of paint due to their high water content. They are even safe in dry form and are great for children to use. They are actually permitted on planes because they are non flammable and non toxic.
These days, emulsion paint is made using latex which is water based. As a result, most emulsion paints are not flammable and are perfectly safe to use and store at home.
There are some excellent flame retardant emulsion paints available that actively prevent the spread of fires, and these are great options for anyone decorating their interiors.
Latex paints are water based and are therefore not flammable substances. When it dries, latex paint has a rubbery feel to it but it is not flammable even in this solid form.
Glass paint is water based and is therefore not flammable. Even when dry it remains non flammable and safe to use.
Chalk paint is water based and therefore non flammable. It is actually considered to be a fire retardant paint that actively slows and stops the spread to flames.
Fabric paint is water based and therefore non flammable. It is very safe to keep around the house as it is non toxic as well and does not have a nasty odor.
Most wall paints that you might use around the house are latex paints and are therefore water based. Water based paints do not contain solvents that will catch alight easily and are therefore not flammable.
Are Paint Cleaners Flammable?
The liquids used to clean and work with oil paints can pose a fire risk. Paint thinner, turps and white spirit are combustible, and the rags you use to wipe oil paint can be highly flammable and should never be left lying around.
How To Store Flammable Paints Safely:
As long as you follow the proper precautions and safety procedures, it is perfectly safe to use and store flammable paint at home and at work.
The dangers arise when you are storing a large amount of flammable paint in one place, because if the paint were to catch flame then it could cause a large scale fire. This is why you should always:
- Keep flammable paints away from heat sources and fire
- Keep flammable paints in a paint store away from main buildings
- Do not store more than 25 gallons of flammable or combustible paint in one room (unless it is a specialist storage compartment).
- Keep flammable paints far from the reach of children - in a locked room or high up on a shelf where it cannot be reached.
- Keep flammable paint containers properly sealed between uses to prevent fumes from leaking out.
- Dispose of old or damaged paint containers responsibly and promptly.
- Keep areas where you are using paint well ventilated. Opening windows and doors will prevent a build up of potentially toxic fumes.
- Never swallow or consume any kind of paint (except food coloring) and be sure to keep paint away from your eyes and delicate skin areas.
In the case of a paint fire you should:
- Call 911 and ask for the fire department if your fire is getting out of hand
- Call 911 and ask for an ambulance if anyone has been hurt or injured due to flammable paint
Most house insurance covers fires that are started by flammable paints, however all polices differ so always be sure to check the small print.