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Interflug
25th May 2008, 08:23
Noise levels are a major factor for the stress level created at any work place.

I'm looking for reliable data about noise levels inside of today's A/C during cruise. Let's say measured at the position of the pilot's head and another measurement in the last row of the cabin. Since noise measurements are tricky to compare, because the level is inverted proportionally to the distance to the emission source and also different weighting curves (A, C etc.) are used, it is tricky or impossible to compare even the little published data that is available.

Is there an industry norm out there how SPL measurements must be taken, that the A/C manufacturers have to comply with when publishing noise level data?

Have any of you internal data, that could be of interest here?

Thank you.

Willit Run
25th May 2008, 09:43
WHAT ? Speak up please!

Bobbsy
25th May 2008, 10:27
Well, funnily enough....

By profession I was an audio engineer. Most normally, when considering the risk and nuisance of sound, the "A" weighting curve is the one quoted because it most closely mirrors the response of the human ear.

Bored on my last long haul flight, I dragged my B&K meter out of my hand luggage and did a measurement in the cabin which worked out to be 79dB(SPL) A weighted. This was 5 seats from the rear of an Air New Zealand 744, with the measurement taken during a "sleep" phase of the flight so there was little or no passenger noise in that reading. If you want to get really precise, I was seated in an inboard aisle seat so away for the exterior "skin" of the aircraft.

Hope this helps. If it wasn't for the rules on flight deck visits, I'd offer to do the "pilots head" measurement for you in return for a spell in the jump seat! Ah well, thanks Osama for spoiling my aviation interest hobby.

Bob

Interflug
25th May 2008, 11:08
Thanks Bobbsy. EU-Law requires the employer to supply noise protection equipment to the employee when the average SPL is >80 dB (A) over 8 hours. Over >85 dB (A) the use of such equipment is mandatory. Now for a 12 hour intercontinental flight, that levels would be even lower. Just imagine all the flight crews wearing those big noise protection headsets. :sad:

Interesting to know, that noise levels present in today's long range airplanes are considered to cause at least temporary hearing impairments.

stiffwing
25th May 2008, 11:48
The airline that I work for has recently installed noise-cancelling headsets on their 767 fleet after years of complaints based around squealing / noisy No. 1 windows.
I am curious... does your airline have noise cancelling headsets on their 767 fleet?

Telstar
25th May 2008, 12:09
EU-Law requires the employer to supply noise protection equipment to the employee when the average SPL is >80 dB (A) over 8 hours. Over >85 dB (A) the use of such equipment is mandatory.

I stand to be corrected, but am quite certain that this does not apply to transport workers. I value my hearing, so bought the best ANR headset money could buy and wear it from pushback to parking brake set!

A330AV8R
25th May 2008, 12:38
noise cancelling ??? I got my 100 $ telex off Ebay works fine , flew with a guy the other day who insisted on keeping his BIG sets on for 10 hours . . .

:ooh: