noise reduction headsets or special earplugs?

[Oasis]

Hi all,
Don't certain if this is the right forum for this, but here it goes.
Are there any 747 or 777 drivers who use one of those noise reduction headsets that can plug in the regular headset plugs or specially fitted earplugs?
Which ones are the best?
(and, if so, where can you order them? I live in asia...)

Just trying to make my ears last a little longer..

Cheers,

Oasis.


------------------
Please don't tell Mum I'm a pilot, she thinks I play piano in a whorehouse.

[wallabie]

Can't hear you, speak louder !!!!!

When I was flying the /400, we were wearing headsets the whole time. I think it had more to do with where the loudspeaker are located ( I understand it's the same on the 777 ) than the aircraft being really noisy.
On the 320 we use the headset up to 10 000 ft and then are on loudspeaker and it's fine. Trust me, there nothing noisier than a first generation 320 !

[Strikie]

Ear-plugs work by blocking sound pressure; good ones by up to 21dB. Active noise-reduction headsets work on cancelling out sound/noise within a specific frequency range - the sound is picked up thru' the boom-mic, the noise-reduction circuit generates an out-of-phase signal, and you then hear 'nothing' in that frequency range!!
Apart from cancelling out some of the ambient noise, ANR circuits 'clean' out the inherent noise in the radios (HF reception is almost as bearable as VHF). What this means is that you can have the receiver volume turned down lower and you can hear your other crew members speak.
Try it out for yourself, and you'll find that ANR headsets have loads more advantage over ear-plugs (but ear-plugs are cheaper, much, much cheaper...)

[trevis]

I fly on the 747-400 and initially used the Sennheiser HMEC 25-KA ANR headset, but as there is no voice activated intercom on that airplane I ended up uncovering one ear in order of beeing able to undertsand the other guy. I felt uncomfortable becaues one ear was getting the full noise and the other one was more or less completely sealed. I stopped using it. Some colleagues use it though and are happy with it.
Hope that helped

[Nightstop]

The Sennheiser HMEC 45-KA http://www.stopstart.fsnet.co.uk/smilie/sarboy.gif seems to be THE ANR headset to have at the moment, it retails for £390 +vat in the UK. For a comprehensive independent user survey see http://homepage.mac.com/rmnelson/noise/HMEC45KA.html

[Roadtrip]

The 747-200 cockpit is pretty loud. I have a Telex ANR-500 that does a fine job. As I recall, it was about $300. The ear pieces don't seal around the entire ear, so cross-cockpit voice com is still easy. Since I'm an F/O, I usually fly with the left earpiece pulled back slightly. I got mine from www.hartaviation.com. (http://www.hartaviation.com.) Many times they'll send them to you on "approval" and you can send them back if you're not happy with the fit or function of the headset.

I've seen the Sensenheiser headsets and they're outstanding, but very pricey.

[stands1to15]

Don't fly the 747 but just a tiddly Canadair albeit with a noisy cockpit. Our company have a set of Sennheiser HMEC-25 headsets for evaluation but despite everyone liking them the company wouldn't shell out for them. Instead I used the earplug setup for a while but gave up as it was poor at best. Have to use the intercom for the HMEC25 to be at its best but it is good.

[Descend to What Height?!?]

We got some ANR Racall Atlantics about 18 months ago. Wish we had had them 8 years ago when I first started trying to work on our aircraft! May have saved our hearing. They solved the noise problems on Hercules, by keeping it all on the inside!

[OzPax1]

This Interesting thread is of professional interest to me as I work in professional Audio.

Sennheiser are well regarded in the business for their audio equipment. Their headphones are personal favorites of mine and also for a lot of the people I work with. I agree headphones for professional use are quite expensive (£140 on up), but the sound quality and wearer comfort tend to be far superior when compared to cheaper gear. Anyway here is the link to Sennhieser aviation headsets page. www.sennheiser.com (http://www.sennheiser.com/headsets/ac/ac_1c001.htm) :)

[Nightstop]

If anyone's interested I've just ordered a HMEC 45-KA from Germany for 1103 DM (£368) including delivery to the UK. See https://www.sky-fox.com/skyshop.html

[PaulDeGearup]

I did a survey on the F100, coz that's what I fly, at the request of management.

Found that the ambient noise levels were in excess of those prescribed by legislation - Health and Safety At Work Act. Passed info to management as per request. Result - Zip, Zero, Nothing, Nought. It would cost money to provide crews with adequate ear protection.
The good news is, if I, or any of my colleagues, lose their hearing the management, having had the problem pointed out, are negligent if they don't take steps to correct the problem. Hugmonster over to you !

[OzPax1]

Will check on this at work tomorrow, but I’m sure that under UK Health & Safety law 95db is the highest level of sustained ambient noise you are allowed to be exposed for any length of time. Any louder then that and you have a case against your employer. In fact I have to make sure that the headphones I use and supply are fitted with 90db limiters for just that reason.

When your job requires you to have good hearing you make bl**dy sure you look after your ears!

[78deg]

I used some noise cancelling headsets yesterday on a B757-200 on 2 two hour sectors, this was as a test on behalf of the company.
1 The background noise reduction was dramatic, I had not realised before how noisy the FD was.

2 For best effect both ears need to be covered by ear pieces and the FD intercom used.

3 After a while I began to feel nausious, although my fellow pilot was fine. Has anybody else experienced this?

[OzPax1]

As promised I've copied the relevant info from my work's health and saftey intranet site :)

The starting point for considering compliance with the Noise at Work Regulations is where potential exposure to sound levels at or above 85 dB(A)(known as the first action level) or to peak action level or above, is suspected. As a general rule of thumb in an environment with a noise level of 85dB(A), normal conversation is difficult at 2 metres i.e. voices need to be significantly raised. All reasonably practicable measures must be taken to prevent exposure to noise levels between the first action level and the second [90dB(A)]. The use of hearing protection must be considered as a last resort.

Limiting headphones and earpieces should be limited to 93dB(A) unless otherwise stipulated by a risk assessment which has been carried out by acompetent person. The exposure level is based on an 8hour Time Weighted Average.


The Noise at Work Regulations (1989)

Action levels are set as follows:

* first action level - a personal daily exposure equivalent to 8 hrs.
at 85 dB(A). Usually expressed LEP,d 85 dB(A)

* second action level - a personal daily exposure equivalent to 8 hrs.
at 90 dB(A). Usually expressed LEP,d 90 dB(A)

* Peak Action level - a peak sound pressure of 200 pascals (140 dB re
20m Pa)

Terms and conventions used:

Leq is defined as that steady level of sound which would equate to the same
varying level averaged over a given time period.

LEP,d is defined as that steady level of sound which would equate to the
same varying level over an eight hour day. (LEP,d is therefore an Leq quoted
for an eight hour period.)

Leq expresses average sound level during a particular sample period. If the
sample period is carefully chosen to be typical of the noise conditions
present the Leq figure can be extrapolated to give a figure for LEP,d.

When quoting Leq it is important to qualify the figure by stating the time period to which it related.

Some early documents refer to dB(A)Leq(8-hour), but the equivalent simpler term LEP,d is now usually used.

The terms Leq(sample) and Leq(Event) may also be seen, the latter being the value of Leq measured from the start of the first act of a performance to the end of the last act.

Further explanation of terms and concepts are contained in HSE Noise Guides
1-8 and in the Guide to Health, Safety and Welfare at Pop Concerts and Similar Events (see appendix IV, References).

Within the current document the words "average sound level" are used. This
is intended to denote a sample Leq where the period of sampling is chosen by the person carrying out the measurement to be likely to result in a truly representative LEP,d when extrapolated.

Shall and must denote an absolute legal duty.

So far as is practicable implies technically possible without regard to cost.

So far as is reasonably practicable implies weighing the magnitude of a risk against the measures required in terms of time, effort and money to offset the risk.

Exposed means exposed whilst at work.

Exposure measurements take no account of the effect of any personal ear protection used.

Competent person. See Appendix II.

Adequate noise assessment Regulation 4 of the Noise at Work Regulations requires a noise assessment to be undertaken where employees are likely to be exposed to the first action level or peak action levels.

The assessment should be adequate for the purposes of identifying which employees are
exposed and for providing them with appropriate information and to facilitate compliance with regard to the appropriate controls.

Analysis of the main requirements of the Noise at Work Regulations (1989)

Employers' Duties Below 85dB(A) At or above 85dB(A) At or above 90dB(A)

General Duty to reduce risk

Risk of hearing damage to be reduced to the lowest level reasonably practicable

Assessment of Noise Exposure

Noise assessments to be made by a competent person

Record of assessment to be kept until a new one is made

Noise Reduction

Reduce exposure to noise so far as is reasonably practicable by means other
than ear protectors

Provision of information to workers

Provide adequate information, instruction and training about risks to hearing, what employees should do to minimise risk, how they can obtain ear protectors if they are exposed between 85 and 90 dB (A), and their
obligations under the regulations

Mark ear protection zones with notices, so far as is reasonably practicable.

Ear Protectors

Ensure, so far as is practicable, that protectors are

- provided to employees who ask for them
- provided to all exposed - maintained and repaired
- used by all exposed

Employees Duties - Use of Equipment

Employees must, so far as is practicable:

- use the ear protectors provided
- use any other protective equipment provided
- report any defects discovered to the employer

Information, Instruction, Training & Competence

The Noise at Work Regulations require all employees likely to be exposed to
first action level or above or to peak action level or above to be provided
with adequate information instruction and training on certain matters. This
requirement would be adequately covered by the Basic Training andInformation detailed in (1) below.

Competence

The Noise at Work Regulations (1989) refer to competent persons and to what must be achieved. Guidance on what constitutes a competent person and advice on training is set out in the HSE's Guidance Notes to the Noise at Work Regulations and in Noise Guide No. 6.

Generally in safety legislation it is for the employer to judge competence.

To be competent

an individual must have sufficient training, experience, knowledge and other qualities to enable him to properly discharge his duties in health and safety.

The extent of these should be defined
both the employer and the individual should clearly understand the degree and limits of competence involved and can therefore identify the point at which further advice should be sought.

Guidance on the Noise at Work Regulations indicates that the level of
expertise needed will vary considerably with different situations.

Comments ;)

[OzPax1]

The following is a link from the Sennhiser site I posted above. Airline Cockpit Noise (http://http://homepage.mac.com/rmnelson/noise/)

[PaulDeGearup]

Oz Pax, That info should be of benefit to all of us, thanks for that.
Interestingly, the 85dB is a background noise level; to hear speech, either through the headset or directly would require modulation at around 20 -30 db on top of background levels. Therefore, you would be receiving in excess of 105dB into your ear. The first sign of damage would be diminishing high tone response as the high frequency scilla are closer to the entrance of the middle ear than the lower freq bits.