Gas fire closure plate tape as specified in BS 5871 : Part 1 Specification for installation of gas fires, fire/back boilers, convector heaters,and decorative fuel effect gas appliances: Part 1 Gas fires, fire/back boilers, convector heaters. 1st, 2nd, and 3rd family gases, Tape complies with the British Gas specification for sealing tape for gas fire closure plates, PRS 10.