Safety Knights

Yes. Having employees who move around a lot makes it even more important to do full-shift personal monitoring.

From the standard:
1910.95(d)(1)
When information indicates that any employee's exposure may equal or exceed an 8-hour time-weighted average of 85 decibels, the employer shall develop and implement a monitoring program.

1910.95(d)(1)(i)
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.

1910.95(d)(1)(ii)
Where circumstances such as high worker mobility, significant variations in sound level, or a significant component of impulse noise make area monitoring generally inappropriate, the employer shall use representative personal sampling to comply with the monitoring requirements of this paragraph unless the employer can show that area sampling produces equivalent results.

It is important to get as good of an idea of employee exposure as possible because you want to make sure that you're providing adequate hearing protection. It isn't as simply as over/under 90dBA (or 85 dBA).

How do you know what "representative sampling" is? That's a tricky one. I've presented at a few different conferences on exposure assessment strategies. It boils down to whether you want to be "compliant" or to really have a well defined exposure. OSHA does not specifically define what representative sampling means. In letters of interpretation for other standards they say that basically as long as you follow an exposure assessment strategy, you're good to go. Some organizations say they'll do 10% of the workforce. Or guess what their worst case scenario is and sample that. Most OSHA folks would accept that as long as you can speak to it.

If you're interested in some other options for assessing and defining exposures in groups with a lot of variability, let me know, and I'd be happy to post hear or talk offline.

Again Drew and Tim are right on. This is what I have done in the past. They will tell me if it was good!

#1 I went to Plant Engineering and got a plant map! I then do a sound survey. I take several sound meter readings in the plant where people work. I put all the readings on the map and take several readings over time, documenting the reading on the sound meter and the date and time. Any reading of 83 or over. I write in red. I just picked 83 as a safety factor. Always calibrate my sound meter. All our meters and calibrators are in the ISO Gauge Calibration System. Remember sound meters are like cameras as they just take a "snapshot of the sound". You really need a "movie" of sound over 8-hours to make the final determination of a HCP.

#2 After at least 5 readings (usually in excess of 8) I highlight readings over 83 and then target those areas for further testing. Back in the old days I would get the three dosimeters out I had and take 8-Hour sound measurements on workers based in the areas I found above. I would also include workers that went all over like Maintenance and Supervisors. I would all the info on another large plant map! Where I had readings of 84.5 dbs over 8 hours I would designate as in the HCM. I might rent more dosimeters if I wanted to get the study over quicker. With just three in a large plant took awhile!

#3 I did that a couple times I even passed an OSHA CHSO audit. Then one day I had a Corporate EHS Audit, soon after we were bought by a huge Corporation. As a result I got a call from the VP of EHS informing me that my IH days were over! I was told Corporate Policy required health decisions to made after consultation of a CIH, and that included noise surveys. I was told I could still do Step 1 but for Step 2 I had to bring in a CIH. I was then given names of Corp Approved CIHs in my geographic area. When I mentioned the cost, she said, "We know you can do it! And I can, but with employee health we require the 'Gold Standard!'