This Technical Report applies to safety and operational topics for equipment and pipework systems installed within industrial premises which may be used for process and non-process applications such as Heating, Power Generation, Incineration, etc. It is applicable to a range of combustible gases used within an industrial environment. The gas plant may include normal combustion with air and/or oxygen, catalytic oxidation or cracking (e.g. as in a refinery). The user of gas equipment and pipework systems has a responsibility to ensure the safety of the design, of plant operation and plant maintenance. For piped supplies of gas to a site this Technical Report applies to the system downstream of the ‘point of delivery’. The term, ‘point of delivery’ refers to the isolation valve (or combination of regulator and isolation valve) located before or after the metering station, as will be defined by the particular EU member state national legislation. The guidance in this Technical Report may also apply to gases generated for the sites own use, such as coke oven gas, site bio-gas plant, site LPG/air plant etc.