BS 6951:1988

National foreword
Committees responsible
Specification
0 Introduction
1 Scope and field of application
2 References
3 Definitions
4 Specification
Annexes
A Numerical example to illustrate the procedure
B Selected values of median threshold shift and of
   statistical distribution
Tables
1 Values of the coefficient alpha used to determine the
   median value of hearing threshold deviation for an
   otologically normal population of given age
2 Values of the parameters bu and bl used to determine
   respectively the upper and lower parts of the
   statistical distribution of hearing threshold levels,
   centred on the median value, for an otologically
   normal population of given age
3 Values of the multiplier k
4 Values, rounded to the nearest whole decibel, of
   hearing threshold deviation at frequencies from 125
   to 8 000 Hz, expressed relative to the median hearing
   threshold level at 18 years of age, that can be
   expected to be exceeded by fractions from 0,1 to 0,9
   (10 to 90 %) of otologically normal groups of males
   and females, at intervals of 10 years of age from 20
   to 70 years
Bibliography

For the frequency range 125 to 8000 Hz and for groups of otologically normal persons of a given age within the limit of 18 to 70 years inclusive, gives the expected value of median hearing threshold shift relative to a group aged 18 years and the expected statistical distribution above and below the median value.