What is the difference between “fire resistant” and “fire retardant”?

This is a question we get a lot. It is not a weird one, because it is quite confusing. Sometimes the word “fire resistant” is used when the word “fire retardant” should be used, and the other way around. That’s why we from Dutch Microwave Absorber Solutions made this artikel. To make clear what is the difference between these terms. So keep on reading to get rid of the confusion!

The difference between the two terms

The terms “fire resistant” and “fire retardant” are often used interchangeably. This is not quite right, because there is a clear difference in meaning.

The difference is mainly in the tests that are done about fire safety. With ‘fire-retardant’, the fire behavior of a certain material is examined: the material is ignited in a shaped corner arrangement and examined for flame spread, drop formation and smoke development. So there are different classes of fire. You can see which class the fire is in.

‘Fire-resistant’ refers to the entire structures and compartments, such as a wall with a door or steel supporting structure. These tests measured, among other things, how long it takes for the fire to spread to another room (fire penetration) and how quickly a certain temperature is reached on the other side of the room (heat breakdown). You can then talk about a fire resistance of 30, 60, 90 or 120 minutes.

With ‘fire retardant’ you mainly see how the fire of a certain material of object behaves, with ‘fire-resistant look’ you look at the bigger picture and investigate how long it takes the fire in one room to spread to another room.

Should I have a fire-retardant or a fire-resistant product?

Although the two terms mean slightly different things, in practice they are used interchangeably. Also, companies that offer fire-resistant or fire-retardant products, use both terms for the same products. This suggests that in practice there is not such a big difference between fire-resistant and fire-retardant products. This is also correct, if you consider that the difference in meaning mainly relates to the underlying tests. So don’t be distracted by the different names. When purchasing a fire-resistant or fire-retardant product, pay particular attention to the nature of the material you want to treat. Should an entire compartment fire be made from ‘only’ one object/specific material?