Slide 7 of 15
Let's look at the sampling strategy.
The regulation says that The sampling strategy shall be designed to identify employees for inclusion in the hearing conservation program and to enable the proper selection of hearing protectors. The operative word, of course is designed. It implies that some thought be put into it - and that the methodology cannot break down - it must be failsafe.
Therefore to achieve this end it is essential that the method used to identify which workers must be included in a hearing conservation program reflect the worst-case sound exposure potential to which those workers could be routinely exposed. Using a blind sampling method such as random sampling would require extensive testing to provide this information with a high degree of confidence that all the worst case work assignments were identified. The sampling method must also assure that the desired conditions exist in the appropriate proportions in the period of observation.