A pressure gauge of minimum dial size of 10 cm shall be provided in the manifold to indicate the gas pressure in the manifold. The pressure gauge shall be suitable for a pressure range 0 to 30 kgf/cm2.

Note: Requirement for LPG as per IS 4576:2021 mentions Vapour (gauge) pressure at 40°C shall not be more than 1050 kPa (10.5 bar). In any case the minimum for the mixture shall be not lower than 520 kPa (5.20 bar) at 40°C, so it is preferred to use a gauge with a pressure range of 0 to 21 bar which is double gauge pressure at 40°C allowed by IS 4576:2021.

A pressure gauge with a range of 0-5 kgf/cm2 shall be provided in the pipeline after the first stage PRV. The joint at which pressure gauge is fixed shall be thoroughly checked for leakage. Millibar pressure gauges (0-500 millibar) shall be provided in the pipelines after second stage PRV.

Note: According to IS 6044 Part 1, the standard stipulates that the pressure in the pipelines should never exceed 1.5 kg/cm2 under any circumstances. Given this guideline, it would be permissible to use a pressure gauge with a range of 0-4 kgf/cm2 in the pipeline after the first-stage PRV. This range is slightly more than double the allowed pressure, providing a safety margin for instances where back pressure may occur in the line.

The Millibar pressure gauges can be provided in the pipelines after second stage PRV as per the pressure requirements of the combustion equipment.