KST – KROMSCHRÖDER SYSTEM TECHNOLOGY
5.2.2.1 Manual isolating valve
A manually operated isolation valve shall be fitted upstream of the first control device in the gas circuit. Manual isolation valves shall be so designed or positioned as to prevent inadvertent operation but shall be easily accessible and capable of rapid operation when required.
If technically applicable, only manual isolating valves complying with EN 331 shall be fitted. For valves outside the scope of EN 331, the safety requirements detailed in EN 331 shall be met at an equivalent level.1)
They shall be so designed that the “OPEN” and “CLOSED” positions are readily distinguishable (e.g. a 90° turn valve if applicable and available).
The following chapters are printed with the permission of the DIN Deutsches Institut für Normung e.V. (German Institute for Standardization). For the implementation of the DIN Standard, the version with the most recent issue date is deemed authoritative. This is available from Beuth Verlag GmbH, Burggrafenstrasse 6, 10787 Berlin, Germany.
Our note on this Standard:
1) Preference must be given to use of a manual valve. Butterfly valves may be used if they meet the same safety requirements.
