Flame retardant clothing is made from material that prevents flames from developing or delays the spread of fire. The material can be inherently or non-inherently flame retardant:

• Inherent: materials with integrated woven flame retardant materials, made without any chemicals. Despite the number of washes, these materials will always remain flame retardant.
• Non-inherent: the material of this clothing is impregnated with flame retardant chemicals. These lose their effectiveness through use and frequent washing. As a result, it is necessary to add new flame retardant agents during the washing process.

Clothing in this category is tested in accordance with one or more of the following standards:

EN ISO 1161/EN 531: Protection against heat and flames.
Clothing tested to this standard protects against flames and against convection and radiation heat (up to a certain degree).

EN ISO 14116/EN 533: Clothing with limited flame spread.
The material will continue to burn, but to a limited extent (when in contact with flames). After extinguishing the flame, the material will also extinguish.