reference: R139:2007 T.1.6

ID: 01994

part or device, other than an ancillary device, required to ensure correct measurement or intended to facilitate the measuring operations, or which could in any way affect the measurement Main additional devices are: - filter; - device used for the transfer point; - anti-swirl device; - branches or bypasses; - valves, hoses, and in general, all the gaseous piping.