Is Finishing Wax Flammable? (All You Need to Know)

Finishing wax is used to protect wooden surfaces and give them a nice aesthetic. It is a softer finish that is usually used on interior furniture or other applications where a hard clear coat is not necessary. If you are planning to use finishing wax, it is important that you know the potential risks, especially where fire is concerned. This article will go into detail about whether finishing wax is flammable or not and how you can use it safely. 

Is Finishing Wax Flammable?

Yes, finishing wax is a highly flammable product so you must take extra care when using it. You also need to make sure that you properly dispose of the empty tin and any cloths or rags you used when applying it.

What Ingredient Inside a Wood Finishing Wax Can Make it Flammable?

The solvents and petroleum distillates in finishing wax are the ingredients that make it so flammable. Things like naphtha and hydrotreated light are added to the finishing wax to make it softer and easier to apply. These solvents then evaporate as the wax dries, leaving behind the rest of the substances that protect the wood. The presence of these petroleum-based solvents makes finishing wax incredibly flammable.

Will Finishing Wax Catch on Fire when Exposed to a Flame?

Yes, absolutely. Petroleum burns incredibly well, which is why it is used as fuel. So, if you expose the finishing wax, which contains high levels of petroleum-based substances, it will catch fire easily.

Can Finishing Wax Catch on Fire from a Spark?

Although it is less likely, finishing wax could still catch on fire from a spark. The official safety guidelines for these kinds of products recommend keeping it away from any source of fire or sparks, including electrical equipment.

Can Finishing Wax Catch Fire from High Temperatures?

Most finishing wax is not self-igniting, which means that it requires an ignition source to set on fire. However, if it reaches its flash point (the lowest temperature at which vapors will ignite when exposed to an ignition source) the risk of fire is much greater. So, if you leave it in high temperatures, it may not light on its own, but it only takes a very small spark to cause a big fire, so it needs to be somewhere relatively cool.

If I Leave Finishing Wax in the Sun Can it Catch on Fire? 

Again, the sun alone will not cause the ignition, but it will heat the finishing wax and prime it for ignition, so the risk of fire is much greater. If the can is left open and sunlight is reflected directly onto the wax, this could potentially create a source of ignition too, so keep it out of direct sunlight. Finishing wax can also create an exothermic reaction with the air if left open, and this may also be enough to ignite a fire.

What is the Flash Point of Finishing Wax? 

The flashpoint of finishing wax varies depending on the product, but they tend to be quite low. These are the flashpoints of some popular finishing wax brands:

• Rust-Oleum Furniture Finishing Wax – 14 degrees Celsius
• Minwax Finish Wax – 42 degrees Celsius
• Osmo Wood Wax – 60 degrees Celsius

Although the values vary, you can see that the flashpoint is relatively low, especially for products like the Rust-Oleum wax. So, leaving the wax in a hot environment will quickly make it a fire hazard.

Is Finishing Wax Flammable when Dry?

No, it is not the wax itself that is flammable, it is the solvents used to soften it. When the wax dries, these solvents evaporate, leaving behind only the wax. Once it has fully cured, your finishing wax should be safe and will not be a fire hazard.

What’s the Safest Way to Dispose of Finishing Wax?

Finishing wax must be disposed of correctly to avoid fire hazards and also prevent damage to the environment. Putting it in your household bin is very dangerous because it will contaminate the environment and it can easily get hot and start a fire. Avoid putting it into drains or anywhere else it could enter the water supply too. 

Your local authority should have a process for disposing of hazardous products, so get in touch with them and follow their guidelines. 

Are Rags or Brushes with Finishing Wax on them Flammable?

Yes, in fact it is often the rags and brushes that cause a fire rather than the can of wax because people don’t realize how dangerous they are. The rag provides fuel for the wax, which can easily ignite if left out in the sun or thrown into the bin. To avoid this, you should lay the rags and brushes out to dry on a non-flammable surface, away from direct sunlight. This allows the solvents to dissipate before you then throw them away or clean them properly. 

How Should You Store Finishing Wax? 

Finishing wax should always be stored in a cool, dry area away from excessive heat and direct sunlight. It should also be far away from any potential sources of ignition, so anything that generates sparks, flames, or heat. Always seal the can properly and store it upright to stop wax from leaking out.

Consider other substances that are stored nearby too. Avoid keeping finishing wax with lots of other flammable solvents, any strong acids or alkalis, and any oxidizing agents. 

How Do You Safely Put Out a Finishing Wax Fire? 

Finishing wax will produce a thick black smoke which can be incredibly dangerous when breathed in, so you must be very careful when approaching a fire. Use alcohol-resistant foam, CO2, or powder fire extinguishers. A water spray can be effective too, but avoid a strong jet of water as this will make the fire worse.

If you have a fire extinguisher on hand and you can control the fire quickly, that’s fine. However, if it gets out of control, call the authorities and don’t take unnecessary risks.

Final Thoughts 

Once it has cured, finishing wax will no longer be flammable because the solvents have evaporated. However, it does pose a serious fire hazard when you are applying it. It is crucial that you store it properly and dispose of rags and brushes properly. Don’t cut any corners and always follow the safety guidelines on the tin to reduce the risk of fires.