Firemaster is a fabric comparative to Proban treated cotton / polyester fabrics. It uses a Pyrovatex treatment from Ciba Speciality Chemicals, a Swiss company.
The fabric is used a lot by the offshore oil rig industry for overalls, but it is also available in lighter weights to make shirts and trousers from.
The fabric is tested to EN531 and EN470. An antistatic version is also available to EN1149. Arcaware has not seen any test results for the fabric against electric arc, but given its construction the performance against electric arc should be similar to the Megatec fabrics offered by Klopman.