The difference between flame resistant (FR) and arc flash or arc rated (AR) clothing is clear, but many professionals make the mistake of choosing FR clothing with the assumption that they will be safe should a fire occur. Both arc flash and FR clothing aim to protect workers from burn injuries relating to open flames, sparks, and other possible fire hazards. Each follows different standards and classifications on the different levels of protection they provide.
FR clothing is made of materials that naturally resist burning, melting or ignition while helping to insulate against heat. AR clothing should be worn when working near electrical equipment or anywhere arc flash hazards can occur. The garments should come with an official arc flash rating on the tag. This shows the wearer that the clothing has been properly tested against the hazard in question.