Avalanche Awareness - It's no joke......

Admin wrote:
Given that a lot of modern smart-phones now use Wifi as well as mobile spectrum I find it hard to believe that interference can be eliminated completely. I'm open to being convinced but it does appear that the manufacturers feel they're playing safe with the advice above.

Advice about fields generally has been in transceiver manuals forever, tests show around 30-40 cm separation from metal objects, power sources etc. Even though power cables can be a particular problem but this is not the large effect that has been suggested, a whole variety of terrain factors can alter signal return as can transceiver orientation.

Classically what the novice user does is hold the transceiver rock steady in coarse search modes which is bad and then wave it around erratically in fine search which explains a lot of the oddities people see. An experienced user can fairly quickly correct for most effects and they don't cause a hiccup in searches.

Mobile phone guidance was pretty much entirely based on an incident 5 years ago in Pra-Loup and it's been established in later investigations of that incident that there was no connection with mobile phone interference, the director of piste security resigned later in fact. As a precautionary principle guidance to guides and leaders was altered and information in handbooks updated, you'll see that disappearing over time. It will remain a hard to dispel story in greater public awareness as these things tend to be.

So we've established mobiles definately can effect the directional search on a digital multi antanna beacon.

We've also established the transmitting beacon can theoretically be effected in specific circumstances (ie. when the phone is searching for a signal) - though this side of the interference problem is yet to generally accepted and is likely to be of far less impact anyway - the scope of this problem is likely to be around 10-15cm of spike deflection in a worst case scenario - still, a real (or theoretical) possibility of 10-15cm deflection is still a possible negative factor which could mean more probing. So whether its proven or not and however unlikely it is to occur in a real world situtaion its something that can easily be avoided at no cost and no investment of time.

So... for the searcher its proven and for the transmitter its theoretically possible in certain situations. The precaution against both instances costs nothing and takes about two seconds - therefore for me its a total no brainer. Swith the thing off! I really din't see there is any argument - however small the risk involved is, if there is a cost and time free precaution that can be taken, why would you not take that precaution?

ise wrote:
It will remain a hard to dispel story in greater public awareness as these things tend to be.

Why does it need to be dispelled? Whos to say there won't be a problem with furute models of phone or beacon? Do phone manufactures rigourously test every new phone against every beacon on the market? Of course not! Its simply good practice. Every model of mobile that comes on the market is slightly different - whos to say one particualar combination of mobile and beacon won't have a negative interaction. There was a Motorola model a while back that was found to switch a certain Orthovox beacon model from transmit mode to search mode - a potentially fatal interaction between two specific models of beacn/phone.

Its not as if switching your mobile off compromises anything whatsoever - it costs nothing - its there and can be switched on in seconds if you need to make an emergency call. It simply removes a theoretical, if unlikely source of problems in an emergency situation.

Nagrjuna wrote:So we've established mobiles definately can effect the directional search on a digital multi antanna beacon.

We've also established the transmitting beacon can theoretically be effected in specific circumstances (ie. when the phone is searching for a signal) -

You quoted one of the manufacturers explicitly stating that to be untrue.

If this were a problem then we'd be seeing a lot of incidents and we've not seen a single one, the only one ever reported was fond to be spurious. I know from experience searching many, many times this is not an issue.

I'm guessing you're one of those people that simply likes to argue for the sake of it. I don't think I posted anything contradictory and don't want to get into an argument about it - I only feel the need to reply because in this case you're actively telling people to disregard part of the safety advise patrollers, manufacturers and trainers routinely include in documentation based on your personal views on the subject. If you don't agree with the standard advice don't follow it - but don't encourage others to do the same!

We wouldn't have to be seeing "lots of incidents" for this to be a potential problem factor. Even if this had been a factor in 90% of burials but only added a few more seconds to search time or required a few more probes to pinopoint a victim we would still not have had the numerous confirmed reports you seem to require before taking a simple cost-free precation. You can't tell whether a rescuer started probing 20cm out because of interference - or whether the directional search was slightly compromised adding a few more vital secnonds to a search. Thats why the beacon manufacturers advise you to switch off, piste patrol searchers do so as a matter of course and many avalanche training courses include the advise when training. They err on the side of safety due to the potential of a problem that could compromise a search however marginally.

If you want to ignore the advice then do so - but as I said don't encourage others to do the same no matter how right you think you are.

Nagrjuna wrote:I'm guessing you're one of those people that simply likes to argue for the sake of it.

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If you want to ignore the advice then do so - but as I said don't encourage others to do the same no matter how right you think you are.

No, what I am actually is one of these people who's actually professionally trained and qualified in avalanche safety.

ise wrote:

Nagrjuna wrote:I'm guessing you're one of those people that simply likes to argue for the sake of it.

.................

If you want to ignore the advice then do so - but as I said don't encourage others to do the same no matter how right you think you are.

No, what I am actually is one of these people who's actually professionally trained and qualified in avalanche safety.

So?

You're still telling people to ignore the advice of other professionals in the industry on the basis of your own views (or your particular training) on the subject!

If you, from your experience, don't want to act on that advice then don't, but don't go round telling others to do the same.