Specification of materials for, and construction and pressure testing of boilers of normal and high output for use with domestic solid mineral fuel appliances.Cross References:BS 21BS 779BS 855BS 1252BS 1387BS 1449:Part 1BS 1449:Part 2BS 1452BS 2640BS 2870BS 2901:Part 3BS 2926Health and Safety at Work etc. Act 1974