Posted By GavinR Hi guys, having a small interpretation issue under PSSR. I have 2 conflicting pieces of guidance regarding pressure regulators and flash back arrestors and their application under PSSR and requirement for WSoE. The ACOP states in Appendix 1 diagram WSoE only applies where Pressure system is steam or has pressure x product of 250bl or more. So i understand that to mean also that any protective device on a pressure system below 250 bl will not be required to have WSoE. However a HSE document i was reading regarding regulators states if the the regulator acts as a protective device in a stationary system then it does need to included in a WSoE. Think i been reading to many sources of information and starting to get confused. Can anyone help me out with this? If it does not need to be included in WSoE then does its supply just need to be replaced every 5 years? cheers

Posted By Dave Daniel Hi Gavin: The Pressure systems regs have a long and sorry history. In their original form there were many in industry who had grave concerns about them. The Motor Industry was particularly concerned and I represented them at meetings with the CBI. As part of one exercise I personally counted 120+ pressure regulators on one in-line transfer machine at Longbridge and at the time we had over 100 machines of this type alone across Rover, along with 25 miles of air mains at Longbridge, all outside the old Factories Act inspection requirements. The normal standard at the time was to put a regulator, safety valve and filter on each connection point. Given that the HSE at the time could produce no evidence of any failures of compressed air systems, we were very concerned with the potential cost and benefit (or lack of). The Written Scheme is not cast in stone and the eventual idea was that only those regulators and safety valves which actually stopped the system bursting should be included. In practice, this is typically the ones at the air receiver or compressor. This excluded all the ones provided on machinery or just for control purposes. Does this help? Dave

Posted By GavinR Thanks dave, what we have is a number of vessels supplying: 1) Hydrogen 2) Acetylene (packs fitted to fixed pipework) 3) oxygen 4) nitrogen All these gases are supplied to welding processes and furnace via fixed pipwork. What i'm trying to determine is the requirement for these proetective devices to be included on WSoE or do we simply need to follow guidance stating the yoy replace all regulators and flash back arrestors every 5 years. I'm reading conflicting guidance on this i believe. cheers