Method of ISO 1999

Estimation of hearing impairment due to age and noise

8hr Normalized Sound Level
Years of exposure

Enter data in each box above, then click button below

Result = %


1] Exposure to high noise levels could always be dangerous to an individual even where a low risk of hearing loss is found for a population. Do not therefore assume that a low risk as indicated by this program is safe.

2] No input form constraint checking - be careful to input correctly

3] HTLAN is the Hearing Threshold Level (HTL) {at the relevant frequencies} associated with age and noise

4] 8hr Normalized sound level is the A-weighted sound exposure normalized to an eight hour day.

5] The Result is the percentage of the male or female population that will attain or exceed the HTLAN for the given input parameters

6] Reference should be made to ISO 1999:1990 for full details

7] The American Standard adapted from ISO 1999 is ANSI S3.44 -1996 (ASA 122-1996)

8] The pre-ISO 1999:1990 British Standard, BS 5330:1976, gives tables for easily estimating the risk of hearing handicap due to noise exposure (for hearing threshold level 30dB, mean of 1, 2, 3kHz). Generally the risk is found to be slightly lower in BS5330 than ISO 1999

9] JavaScript Browser such as Netscape v.2 or better required

Go To My Main Home Page

Fill Out My Feedback Form

Copyright © RadioMods 1997-2016