NF T54-066:1987 PLASTICS. POLYETHYLENE FITTINGS WITH ELECTROWELDABLE INSERTIONS FOR GASEOUS COMBUSTIBLE DISTRIBUTION NETWORKS. SPECIFICATIONS AND TEST METHODS.
2010NF T54-065-1:2010 Plastics piping systems for the supply of gaseous fuels - Polyethylene (PE) - Part 1 : general.
0000 NF T54-065-1:2003
1987NF T54-066:1987 PLASTICS. POLYETHYLENE FITTINGS WITH ELECTROWELDABLE INSERTIONS FOR GASEOUS COMBUSTIBLE DISTRIBUTION NETWORKS. SPECIFICATIONS AND TEST METHODS.