BS 6644:2005+A1:2008
Specification for installation of gas-fired hot water boilers of rated inputs of between 70kW (net) and 1.8 MW (net) (2nd and 3rd family gases)

https://doi.org/10.3403/03291691 (published 08/07/2005)

BS 6644:2005+A1:2008 is maintained by GSE/30. This standard is available from the following sources:

Other historical versions of this standard document also exist: