Comprises Part 1:Section One and Parts 2, 3, 4 and 5 of 4A 4.Cross References:BS 131:Part 1BS 131:Part 2BS 131:Part 3 BS 131:Part 4BS 240:Part 1BS 240:Part 2 Supplement No. 1 to BS 350:Part 2:1962BS 427:Part 1 BS 427:Part 2BS 891:Part 1BS 891:Part 2 BS 1610BS 1639BS 3846BS 4175:Part 1 BS 4175:Part 2PD 5686Replaces BS 3A 4:1949.Partially replaced by BS 18:1987.Incorporates the following:AMD 319 published 01 January 1969AMD 7710 published 15 June 1993AMD 7919 published 15 November 1993