Provides recommended design and measurement methods for use by local authorities and administrators of public buildings and sports stadia, purchasers, designers, manufacturers and installers, for the correct installation of AFILS with an acceptable performance level and good reliability for use by persons who are hard of hearing.Cross References:BS 381CBS 415BS 5839:Part 1BS 6004 BS 6083:Part 1BS 6083:Part 4BS 6231BS 6360BS 6500BS 6840:Part 1BS 6840:Part 3 BS 6840:Part 8BS 6840:Part 10BS 6840:Part 16 BS 7671BS 4808:Part 2IEC 118:Part 4DEF-STAN 61-12:Part 6