ISO 16923:2016 covers the design, construction, operation, inspection and maintenance of stations for fuelling compressed natural gas (CNG) to vehicles, including equipment, safety and control devices. ISO 16923:2016 also applies to portions of a fuelling station where natural gas is in a gaseous state and dispensing CNG derived from liquefied natural gas (LCNG) according to ISO 16924. ISO 16923:2016 applies to fuelling stations supplied with natural gas as defined in local applicable gas composition regulations or ISO 13686. It also applies to other gases meeting these requirements including biomethane, upgraded coal-bed methane (CBM) and gas supplies coming from LNG vaporization (on-site or off-site). ISO 16923:2016 includes all equipment for downstream gas supply connection (i.e. point of separation between the CNG fuelling station piping and the pipeline network). Fuelling station nozzles are not defined in this document. ISO 16923:2016 covers fuelling stations with the following characteristics: - slow fill; - fast fill; - private access; - public access (self-service or assisted); - fuelling stations with fixed storage; - fuelling stations with mobile storage (daughter station); - multi-fuel stations. ISO 16923:2016 is not applicable to domestic CNG fuelling devices without buffer storage. NOTE ISO 16923:2016 is based on the condition that the gas entering the fuelling station is odorized. For unodorized gas fuelling stations, additional safety requirements are included in Clause 10.