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Orange_Medic
22nd May 2019, 07:06
Morning everyone,

Currently fly front left seat in UK air ambulance and having previously flown in another aircraft that had ANR fitted as standard now fly in a cab that doesn't. Have asked the question about having Alpha helmets having ANR fitted but was told would be too expensive. Is there any legal requirement or such that would require employers to provide better protection if available? Pro's and Cons for ANR?

Any replies gratefully received

Autonomous Collectiv
22nd May 2019, 10:00
Thumbs down for ANR, go CEP immeasurably better

lead and lag
22nd May 2019, 10:01
Hi, no requirement as far as I know. I flew North Sea and the operator provided David Clark headsets (non ANR) which were dreadful especially after 5 or 6 hours flying. I ended up getting my own ANR headset and then claiming back the tax portion through HMRC, they do allow that. So not sure if you can do that ie purchase your own helmet, claim the non ANR portion through work and claim the extra tax portion back - it will still cost you but not as much

Orange_Medic
22nd May 2019, 10:26
Hi, no requirement as far as I know. I flew North Sea and the operator provided David Clark headsets (non ANR) which were dreadful especially after 5 or 6 hours flying. I ended up getting my own ANR headset and then claiming back the tax portion through HMRC, they do allow that. So not sure if you can do that ie purchase your own helmet, claim the non ANR portion through work and claim the extra tax portion back - it will still cost you but not as much

Cheers both, tad annoying as makes sense to protect hearing with something if it's available?!?

Senior Pilot
22nd May 2019, 10:41
There is plenty on CEP's in CEP-Communication Ear Protection (http://www.pprune.org/rotorheads/364122-cep-communication-ear-protection.html) :cool:

Hot_LZ
22nd May 2019, 11:03
An operator isn't going to spend unnecessarily if they don’t have to sadly. If there’s no legal requirement they 9/10 won’t do it. We could learn a lot from our Norwegian friends about looking after the work force but don’t see it happening on this side of the water.

LZ

homonculus
22nd May 2019, 11:31
No requirement save that all employers have an over riding duty to protect their employees from harm. If they fail to do so and employees are harmed, legal action can be successful and HSE may become involved.

Ford were criticised by the trades unions at Dagenham 20 years ago. The unions arranged for hundreds of workers to have audiograms and consultations with ENT consultants to build up a case that overall their hearing was worse than the normal population due to the noise on the factory floor. Given you are but one person, it might be worth seeking out how this action was resolved. Your employer might be interested.....

Stitchbitch
22nd May 2019, 11:36
ANR pros: Good level of sound attenuation, you can still hear aural clues despite the noise cancelling, R-R solution.
ANR cons: Very Expensive for OEM approved system, hearing loss, maintenance intensive in the long term, not easily retro fitted.
Mini CEP: Very good levels of sound attenuation, easily retro fittable, affordable, not maintenance intensive.
Mini-CEP cons: Almost too good - aural clues can be lost, you stick them in your ears - some people don't get on with this, can stay in ears if fitted by the ham fisted. ;)

Gentex now have wire free cep available, which gets rid of the cables, this combined with something like the Pro Flight Gear 'zero G' comfort upgrade would be something that I'd happily recommend to Alpha helmet wearers.

If you're in the UK give these guys a call, Key Survival they distribute and service Alpha helmets on behalf of the OEM, and come highly recommended.

aa777888
22nd May 2019, 17:31
ANR cons: ...hearing loss...
Can you elaborate on exactly what you mean by "hearing loss"?

Stitchbitch
23rd May 2019, 08:20
Can you elaborate on exactly what you mean by "hearing loss"?
ANR doesn't stop high frequencies, these can damage hearing.

tucumseh
23rd May 2019, 10:28
ANR doesn't stop high frequencies, these can damage hearing.

The damaging frequencies are determined by a noise survey in each aircraft type, and (especially in the military) each Mark. The basic ANR is then adapted which, in practice, is often component value changes (analog ANR) or via software (digital ANR). The audio cues required in each type are part of this survey, and often a compromise is needed. But, typically, the damaging frequencies (as opposed to annoying) are around 800-900Hz, from transmissions. In other words, you just don't go out and buy an 'ANR'. You need one that matches the aircraft and, especially if it's an integrated system, approved by the aircraft design authority. The obvious example to me is that the Sea King AEW systems (both analog and digital) were superb, but of no use whatsoever in a Lynx. Purely by chance, they worked very well in a Sea Harrier.

Stitchbitch
23rd May 2019, 11:24
That works well for government/military where these sort of things are well considered and organisations have the funding to carry out noise surveys (RAFCAM/QQ).
In relation to the helmet mentioned by the OP, from experience of being on both sides of that particular fence, standard practice for civilian operators is often to use the cheapest available system (often a DC clone), and self install in a lot of cases. Individual pilots who often have to self fund their own kit can't see the logic in spending almost twice as much as a base helmet to gain this capability. CEP on the other hand (or custom moulded VAMPS) provides a good trade off between protection and cost - and unfortunately cost is often what the choice comes down to.

tucumseh
23rd May 2019, 12:04
Stitchbitch, you are too kind to the government/military!

My worry here is that aircrew simply buy an off-the-shelf broadband system, unsuitable for their purpose. I know of at least two well-known ANR manufacturers who completely toppled when told their broadband systems, typically used in the back of army vehicles or for passengers, wouldn't get past first base in any aircraft design review. One in 1994, the other in 2012. I could understand the first, as it was early days, but the second was alarming.

The last air ambulance I was in, in 2001, they used HISL helmets. (Hereford & Worcs). The same company would provide their helmets with the superior MoD ANR fitted, subject to the survey/approvals mentioned. I know that in 1996 the cost of a made to measure helmet increased by about 30% with ANR mod. You make a good point about self-funding kit. Although I shudder at the attitude of employers who expect this.

aa777888
23rd May 2019, 14:43
ANR doesn't stop high frequencies, these can damage hearing.
Ah, now I understand. There really isn't that big of a difference between modern, well-fitted, ANR headset technology and CEPs. That doesn't mean there is no difference, nor, more importantly, does it mean that all ANR earcups and headsets are well-fitted. However, given proper attention to detail there is generally only a 5dB difference, give or take, at the higher frequencies, which is not a huge amount.

People often have better results with CEPs because they are almost always well-fitted by definition. Comply Foam earplugs automatically expand to provide consistent and repeatable sealing of the ear canal. The same is not always true of earcups providing a reliable and consistent seal against the head. (BTW, Comply Foam earplugs consistently outperform custom molded earplugs.)

Of course the best answer is "use everything". CEPs surrounded by ANR ear cups surrounded by a helmet is the best answer. This can be well approximated by wearing regular foam earplugs under an ANR headset (and helmet, if worn). However, the highest performing solution is not always the most convenient nor the least expensive. There are many pilots, including myself, who will choose convenience over performance.

FWIW, in my flying I use either a DC ONE X or a Clarity Aloft, the latter being a CEP headset without the ear cups. They both work similarly in terms of noise reduction. The Clarity Aloft is super comfortable in the summer time, but not as convenient as the DC's. I ought to try putting in a set of foam plugs under the DC's, but sometimes I'm afraid I won't be able to hear potentially scary noises good enough.

Miles Gustaph
24th May 2019, 10:29
No requirement save that all employers have an over riding duty to protect their employees from harm. If they fail to do so and employees are harmed, legal action can be successful and HSE may become involved.

Ford were criticised by the trades unions at Dagenham 20 years ago. The unions arranged for hundreds of workers to have audiograms and consultations with ENT consultants to build up a case that overall their hearing was worse than the normal population due to the noise on the factory floor. Given you are but one person, it might be worth seeking out how this action was resolved. Your employer might be interested.....

The HSE have no authority over commercial aircraft flying, their certification criteria or their safety in flight; as such as long as the aircraft remains in compliance with its type certificate then the aircraft is fit for purpose.

Perversely if an individual has a belief that the operation of an aircraft, or its equipment in flight poses a risk to their health they are required to report it through their operators reporting system, failure to do so will go against you if you pursue a claim, for example for hearing loss, in the future as you failed to give your employer the opportunity to remove you from the 'risk' and failed to take reasonable steps to protect yourself. For aircrew it's even more strict in that they are required to make a declaration at each medical for any new issues, again failure to declare will go against you and declaration may affect your employment opportunities.

Aviation safety is about protecting the integrity of the aircraft, it is not about making reasonable adaptation to each and every member of crew and each and every passenger unfortunately.

homonculus
24th May 2019, 15:00
You are of course assuming OP is aircrew and employed by the AOC.......