NF P16-369/IN1*NF EN 14982/IN1:2010 Plastics piping and ducting systems - Thermoplastics shafts or risers for inspection chambers and manholes - Determination of ring stiffness.
2010NF P16-369/IN1*NF EN 14982/IN1:2010 Plastics piping and ducting systems - Thermoplastics shafts or risers for inspection chambers and manholes - Determination of ring stiffness.