Posted By Frank Hallett Good evening Steve You don't identify what sort of plant you're referring to, but the general principles will be the same for all plant. You should go to L22 [PUWER inc ACoP] and start at Reg 7, go to Reg 12, then Regs 19 & 20, then 22. If it's a Press, read all of Part IV; if it's Lifting equipment, go to L113 LOLER. Frank Hallett

Posted By steve e ashton Frank, Thanks for the pointers, but I was hoping for somthing a little more specific - para 280 of the PUWER guidance is the closest, where it mentions 'restraint' of potential energy - but a check valve in the hydraulic system may be seen as being such 'restraint'... My thoughts are that I would be looking for a mechanical scotch, prop, leg, strut.... The specific machine is an ingenious piece of specialist railway kit that raises itself on a single (machine mounted) hydraulic ram before being swivelled and lowered - its a way for the machine to change direction, and enables the machine to be parked 'off track'. Unfortunately, whilst it's raised, the staff have to place or remove temporary rails... putting them in the hazard zone if the hydraulics fail and the machine falls under gravity. However, the principles are the same for vehicle maintenance lifts, for tipper truck beds, for mewps and scissor lifts and etc etc. Thanks again.... Steve

Posted By Barry Cooper Steve Check valves are not acceptable. You should chock the equipment. Several years ago, we had a major accident where a guy was working under a large reel cutting guillotine when the hydraulic check valve failed, the blade descended and cut all his fingers off. The risk assessment had not foreseen the hydraulics failing, so the company were prosecuted. The new machine has chocks fitted. The injured guy had his fingers re-attached and is ok.