BS 6891:2015 specifies the design, installation, commissioning andmaintenance of gas installation pipework carrying 2nd and 3rd family gas of upto 35 mm (R 1¼) on premises, including residential park homes (2ndand 3rd family gas) and caravan holiday homes (2nd family gas) (see Table 1 andexamples in Figure 1 to Figure 3; see also Figure 4).NOTE 1 The principles of the standard can also be applied to the design,installation, commissioning and maintenance of gas installation pipeworkcarrying 1st family gas.NOTE 2 Annex A gives a method for calculating pipe sizes. Annex B discusses thesulfidation of natural gas installations, while Annex C summarizes the conclusions ofa report on gas in intermediate floors. Guidance on determining whether an areacan be deemed a "protected area" is given in Annex D. Requirements for LPG finalstage regulator and safety devices are specified in Annex E. Annex F discusses theneed for gas pipework design and installation for commercial installations to satisfyregulatory requirements regarding explosive atmospheres.This British Standard is not applicable to:

service pipework and distribution systems;
pipework contained within an appliance;
bulk storage vessels;
LPG pipework installed in leisure accommodation vehicles and foraccommodation purposes in vehicles in accordance with BS EN 1949;
boats, yachts and other vessels;
gas pipework supplying or within appliances having their own gas supply,such as mobile heaters; or
gas pipework supplying or within catering establishments covered byBS 6173.

Cross References:BS 21BS 143 and 1256BS 669-1BS 669-2BS 864-2 BS 1552BS 3016BS 3212BS 4371BS 5114BS 6172 BS 6362BS 6400-1BS 6400-2BS 6400-3BS 6501-1BS 6956BS 7624BS 7671BS 7838BS 8537BS EN 331 BS EN 751-1BS EN 751-2BS EN 751-3BS EN 1057BS EN 1254-1BS EN 1254-2BS EN 1254-4BS EN 1254-5BS EN 1555-1 BS EN 1555-2BS EN 1555-3BS EN 1775:2007BS EN 10216-1BS EN 10216-2BS EN 10216-5BS EN 10217-1BS EN 10217-2BS EN 10217-7BS EN 10226-1BS EN 10241BS EN 10242BS EN 10255 BS EN 10312BS EN 12864BS EN 13349BS EN 13785BS EN 13786BS EN 15069BS EN 15266BS EN 16129BS EN 16436-1BS EN ISO 228-1BS EN ISO 10380ISO 7-1BS 476BS 1494-1 BS 1710:1984BS 3632BS 4250BS 5482-1:2005BS 5482-2 BS 6004BS 6007BS 6173BS 6231BS 7967BS 8313 BS EN 437BS EN 1044BS EN 1763-1BS EN 1949:2011+A1:2013 BS EN 14324BS EN 29453BS EN 60079-10BS EN ISO 10239PD 5482-3Gas Safety (Installation and Use) Regulations 1998Gas Safety (Installation and Use) Regulations(Northern Ireland) 2004Gas Safety (Installation and Use) Regulations 1994Health and Safety (Gas) (Guernsey) Ordinance 2006Building Regulations 2010 (England and Wales)Building Regulations (Northern Ireland) 2012Building (Scotland) Regulations 2004Gas Safety (Management) Regulations 1996Gas Safety (Management) Regulations (Northern Ireland)1997IGEM/GM/6:2011IGE/GM/8:2005IGEM/UP/2:2008 Road Vehicles (Construction and Use) Regulations 1986Caravan Sites and Control of Development Act 1960Caravans Sites Act 1968IGEM/IG/1:2014Dangerous Substances and Explosive AtmospheresRegulations 2002Dangerous Substances and Explosive Atmospheres(Northern Ireland) RPartially replaces BS 5482-1:2005 which remains current