Loss of hearing with age at both ends of the spectrum is perfectly
common. But I don't know whether loss in the range of 80-100 Hz is
within what would be considered normal and particularly for your age.
I'll bet that the Silver Schnozz knows the answer.
Chuck Norcutt
Chris Barker wrote:
> This is really OT ...
>
> Last week pilots of Grob Tutor aircraft were told that were to limit
> their flying to 8 hours a week because of the damaging exposure to
> noise levels above 87dB. The alternatives tried, using foam ear
> plugs, were ineffective (as well as dangerous) because the noise is
> at predominantly at 80 and 100Hz. Our helmets, commonly considered
> decent noise attenuation devices, are also useless for defence
> against such low frequencies; I suspect that it's less a problem of
> sound entering the ear canal, more one of overall vibration. But, as
> usual, I have to admit to being no expert in this area.
>
> The problem arose because the EU forbids extended exposure to such
> levels; it has done so since 2003 or 2005 (not sure about when) but
> the trials in our aircraft have only just been noted (or carried out)
> and there is a sudden panic to limit exposure, and presumably
> liability by my employer.
>
> I pooh-poohed the idea that it was a problem initially, but I am now
> a convert. I have had my ears tested annually for the last 35 years
> and all I have lost is a bit of high-tone hearing. However, it
> appears that we aren't tested for hearing at these low levels and I
> now don't know what damage has been caused to my hearing.
>
> Are there any experts reading this who might comment?
>
> Chris
>
> On 16 May 2010, at 12:00, Wayne Harridge wrote:
>
>>> Add to that the problem we now have with low-frequency noise (80
>>> or 100Hz) and my flying hours will be right down this year.
>>>
>> What's that all about Chris ?
>
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