In practical terms, the most practical thing she can do is wear hearing protection herself
-- or use good moulded earphones that provide a good level of ambient noise reduction, and
then she can play her own music at a sensible level!
To answer your first
question, though, the law is pretty vague about this. There are very strict and well
defined rules about noise exposure to employees (the 2005 Noise at Work act) -- which
would definitely apply to any staff working on the premises (and I bet the 'manager'
doesn't know about it!) -- but nothing really to protect the public.
other issue here is that your trusty Maplin SPL meter -- useful as it is in many
situations -- won't be much help here. The reason is that you need to measure noise
not just peak or short-term averaged SPLs.
The closest I've ever
found to regulations for public sound exposure is in the Health & Safety Executive's
(HSE) Event Safety Guide, where it suggests a maximum acceptable sound exposure is 107dB
LAeq, and a maximum peak SPL is 140dBC. I'm quite certain your gym will be nowhere close
to the latter, and it's quite unlikely to reach the former, to be honest.
However, for the employees, the NaW thresholds are all considerably lower. The 'lower
action level' value defined in the 2005 NaW legislation is 80dB LAeq — which is the
result of continuous exposure to noise of 80dBA for eight hours (or 40 hours across a
working week). 80dB LAeq really isn't very loud at all, and it is quite possible that
workers at your gym are exposed to this kind of noise level if your other half is finding
the music too loud.
Again, your SPL meter won't provide a useful indication
from a sound exposure point of view, but if it is showing slow average A-weighted readings
of 85dBA-ish then it would be worth investigating further. The problem, of course, is that
music is non-continuous, and so the actual exposure will be a lot lower than a slow
average SPL reading.
However, let's assume that the music does constitute a
noise exposure of or over this 'lower action level' of 80dB LAeq. IN that case, the
employer is required by law to do something about it! The legislation actually states
that, "The employer shall ensure that risk from the exposure of his employees to noise is
either eliminated at source or, where this is not reasonably practicable, reduced to as
low a level as is reasonably practicable."
In other words, the employer has
either to turn the music down, or provide his employees with hearing protection, or rota
them in such a way that their personal exposure is reduced below the 80dB LAeq threshold.
And of course, if an employee thinks there is reason the believe that the noise exposure
is over 80dB LAeq, the employer is obliged, by law, to have a formal noise assessment
performed by someone suitably qualified.
The 'upper exposure action' value is
defined as 85dB LAeq, or a peak level of 137dBC for impulsive sounds. If the upper
exposure limit is reached, despite efforts to reduce the source noise and the exposure of
staff to it, then suitable ear protection must
be provided and must
by any members of staff likely to be exposed to the noise.
employees wanting to do that, let alone employers providing wanting to provide the
appropriate facilities and everything that goes with it, which includes training, health
checks and so on...
I wrote a piece about all this for the old SOS
sister-mag, Performing Musician which you can read HERE
It goes into it in quite some depth.
suggest that a quiet word with the manager, asking what noise exposure assessment has been
done for the gym's employees, and drawing his/her attention to the requirements of the NaW
act might put the fear of prosecution into him/her and persuade them to be more
reasonable. If your better half is friendly with any of the staff, then pointing out the
risks to their own hearing and the provisions of the law to protect them might also help
to put pressure on the managment...
By the way, the
cheapest meter I know of that does proper sound exposure measurements is the NTI
Acoustilyser. However, you can hire proper sound exposure meters quite easily and although
you need to be properly qualified to make formal measurements, the basic operation is easy
enough to grasp for an 'interested party'
Technical Editor, Sound On Sound