I did something that I haven’t done for at least 10 years last night. I went to a night club.
I know I’m called “young”, but that’s only because it takes so long to actually become an occupational hygienist, the term “young” is relative. I typically class myself in the category, “too old for nightclubs” in my normal life!
Aside from the poor ventilation, and heat stress impacts, the most obvious hazard (apart from intoxication) was the hazard posed by being exposed to high levels of noise, and it got me thinking. If I was in an industrial scenario, I wouldn’t bother with a noise assessment as the noise was so high, even if you shouted to be heard; you couldn’t hear anyway, so it was obviously over 85 dB(A). Instead, I’d go about the process of hazard reduction and reducing the level of noise. Sounds like the fun police just arrived…yes that’s me.
Let’s exclude the patrons for this scenario, as it’s not their place of work, and focus on the bar staff. They started at 8pm and the club shuts at 12pm. That’s 4 hours of noise exposure. The maximum noise level the bar staff should be exposed to would be 88 dB(A) (assuming that they spent their remaining time in a quiet environment, and didn’t go clubbing afterwards). I didn’t have my sound level meter on me (forgive me this time), but there was no way that noise was as low as 88 dB(A). So are nightclub owners and bar staff aware of this hazard? No one was wearing hearing protection, so the risk was not controlled in the slightest. Are bar staff aware of the risk of developing noise induced hearing loss? Are there measures in place to prevent them from going deaf? Do they receive audiometric assessments to track their rate of noise induced hearing loss? I don’t know, but I’m going to go out on a limb and say probably not…although I’d be delighted to be corrected.
The occupational exposure standard for noise is 85 dB(A) measured as an average over an 8-hour period (and 140dB(C) measured as a peak) which was designed to protect most (but not all) workers from developing noise induced hearing loss. Therefore workplace noise should be kept lower than the exposure standard where reasonably practicable. Typically though, If you have to shout to be heard, then you’ve exceeded the 85 dB(A) exposure standard and you need to do something about it. If you have never heard of this before, this document is a great reference for you.
You can hear what it’s like to have noise induced hearing loss here; it’s not a great thing to be diagnosed with, and remember that there is no cure. So what of the nightclub patrons (including me)? Well noise effects bar staff the same way it affects patrons, so the risk is the same(although enforced through different regulations).
A study published early this year showed that a high proportion of nightclub patrons reported experiencing symptoms related to noise-induced hearing loss after attending a nightclub. In fact over 88% nightclub patrons surveyed experienced tinnitus after leaving a nightclub and 66% suffered impaired hearing the following morning.
The good news is that all of this is preventable. Let’s assume that it would be too much of a fun police thing to do to turn the music down, so alternatively the nightclub owners could look at other controls such as the use of hearing protection, including training, fit testing, and ongoing audiometric assessments.
You can help reduce your risk of developing noise induced hearing loss by being aware of the hazard, limiting the time you are there, or wearing hearing protection to reduce your exposure. You might think that I’m going to recommend that you don’t go to nightclubs as they are too hazardous…in fact, I think we need to encourage more occupational hygienists to go there and help management understand their risk, obligations, and help with control measures…research at its best!