When it comes to noise safety and hearing on construction sites, there seems to be a bit of a gap between the theory of protecting workers’ hearing and the reality of the workers actually being safe.

HPD by darkbuffet

[Image courtesy of Flickr user darkbuffet via a Creative Commons license] Hearing protection devices, or HPDs, can be valuable tools on many worksites, including construction. But if supervisors pay more attention to the noise-reduction rating (NRR) and less on the comfort level of HPDs, they will find that the amount of protection provided for hearing will be not worth the investment.

Donald Garvey writes about conservation of the hearing sense in an article published in the September 2015 issue of Professional Safety magazine, of which I began reporting on in an earlier post last week. Several studies have found recently that construction workers – even those who work outside – are reportedly exposed to high levels of noise over an extended period of time, levels of noise that are above NIOSH’s recommendations but even some are exposed to levels higher than OSHA’s more-lenient standard.

Just think about it for a second. A recent study revealed that 70 percent of workers on construction sites, over the course of a full shift, have a noise-exposure level greater than 85 decibels, which is above the NIOSH standard. And imagine those workers being exposed to that level of noise (which is the equivalent of heavy city traffic) for eight to 10 hours per day every day? Over time, that noise is expected to wear down your ability to hear, and deafness may soon result.

HPDs: Prevalence vs. Use

The most common tool for combating that much noise is what is called an HPD, or hearing protection device. Many of us may also call them earmuffs or ear protectors – they look like headphones from the old days. These HPDs are prevalent and can be easily applied to any construction site for virtually all workers.

However, it seems that studies have shown that HPD use is much lower than it should be. Research revealed that not only is there not 100-percent HPD usage among construction workers, but those who actually use HPDs use them only about 20 to 40 percent of the time in which they are exposed to 85 dB or more of noise during a shift.

When these HPDs are available, why would they not use them all the time? There seem to be several possible reasons (or excuses) for this:

  1. Too uncomfortable to wear. We’ll get into noise-reduction rating (NRR) in a minute, but having more comfortable HPDs with lower NRR may actually be preferable to uncomfortable HPDs with high NRR, because the NPD is only effective when it is actually being used.
  2. Not available. If a worker has to leave his job location in order to get an HPD to wear, he is less likely to actually use it. An HPD must be handed to the worker when he arrives on site or otherwise be readily available for him.
  3. Lack of training. It’s not just about putting on HPDs; it’s about giving workers the information they need to be able to pick the right HPD for them and to use it properly and completely. Empowering workers is a key element.
  4. Too much protection? There is such a thing. If there is too much noise reduction with an HPD, then regular communication among workers or between workers and supervisors (including safety warnings) can be hindered, as outside voices may be too muffled to be understood, and the HPD would then have to be removed, which then exposes the worker to the ambient noises.
  5. Lack of options. You may give workers training to find the right HPD for them, but what good is that training if you only give them one option at a worksite? That one choice could be the best for the general population of workers, but some individuals will have problems with the noise-reduction level and/or the comfort level of the HPD, and thus it won’t be worn.
  6. The climate of safety. If safety is not a priority for the company – instead it offers HPDs but leaves it entirely up to the workers to decide if they want to wear them – then it may not be very important to the workers themselves, especially if an HPD is not comfortable or doesn’t provide the protection wanted or needed.

What is NRR Anyway?

Not all HPDs are the same. All HPDs sell themselves on what is called an NRR, or noise reduction rating. However, be warned that this is not necessarily an actual amount of noise reduction in decibels for everyone who wears them. The rating is usually brought about by machines, which have no sense of hearing themselves but rely on formulas and numbers to come up with NRR. The actual amount of noise reduction can vary according to user, and often the actual reduction is significantly less than what is advertised.

It is recommended by most health and safety standards to have noise levels reduced to 70 to 80 dB to promote safety with hearing while also making communication on the worksite still possible. However, some studies have revealed that workers over the course of a full shift, based on the amount of time they wear HPDs on the job, will see noise-reduction levels be at most 3 dB. Not exactly a solid endorsement for HPD use.

While NRR can be important in determining the potential noise reduction for workers on a worksite, there often can be a need to consider comfort and fit as much or more than NRR. My next post will cover fit testing of HPDs and the difference such a test can make on the efficacy of HPDs compared to only considering NRR alone.