BS ISO 4437-2:2014

This standard BS ISO 4437-2:2014 Plastics piping systems for the supply of gaseous fuels. Polyethylene (PE) is classified in these ICS categories:

• 75.200 Petroleum products and natural gas handling equipment
• 83.140.30 Plastics pipes and fittings for non fluid use

This part of ISO 4437 specifies the characteristics of pipes made from polyethylene (PE) for piping systems in the field of the supply of gaseous fuels.

It also specifies the test parameters for the test methods referred to in this International Standard.

In conjunction with part of ISO 4437-1, ISO 4437-3, ISO 4437-4, and ISO 4437-5, it is applicable to PE pipes, fittings and valves, their joints, and joints with components of PE and other materials intended to be used under the following conditions:

1. the maximum operating pressure (MOP) is based on the design stress determined from the compound minimum required strength (MRS) divided by the C factor, and taking into account rapid crack propagation (RCP) requirements;

2. a temperature of 20 °C as reference temperature for the design basis.

NOTE 1 For other operating temperatures, guidance is given in ISO 4437-5:2014.

For above ground application of pipes conforming to this International Standard, the pipes should be protected by a casing pipe, taking into account any relevant national regulations and installation practices or codes.

This part of ISO 4437 covers three types of pipes:

• PE pipes (outside diameter d_n) including any identification stripes;

• PE pipes with co-extruded layers on either or both the outside and/or inside of the pipe (total outside diameter d_n) as specified in Annex A, where all PE layers have the same MRS rating;

• PE pipes (outside diameter d_n) with a peelable and contiguous thermoplastics additional layer on the outside (coated pipe) as specified in Annex B.

NOTE 2 It is the responsibility of the purchaser or specifier to make the appropriate selections from these aspects, taking into account their particular requirements and any relevant national regulations and installation practices or codes.