The compass on the left has a flipped needle, pointing in the wrong direction. The right-hand compass is indicating the correct northernly direction. Photo: Bob Smith/grough
Mountain experts have identified a new hazard for hillgoers, after analysis of a recent rescue in the Highlands.
The trend in the use of magnets in outdoor clothing could be making compasses flip polarity, with potentially dangerous consequences.
Safety experts said the trend in the use of magnetic closures on jackets and gloves is worrying. The magnets are being marketed as a modern alternative to Velcro or poppers, they said.
But Mountaineering Scotland said magnets are well known for deflecting compass needles, and there is evidence that this may have been the cause of a recent mountain rescue callout, and called for a rethink from clothing designers.
Heather Morning, mountain safety adviser for the organisation, said: “We have reviewed the circumstances of a recent incident in the mountains east of Glen Shee, which involved hundreds of hours of rescue personnel hours and police time.
“A group of walkers were caught in low cloud and headed east instead of west, becoming totally disorientated and ending miles away from a road. Fortunately no-one was hurt – just pride dented – but it could have turned out so much worse had mountain conditions been more severe.
“The reason for the error was the compass. It had been stored in a pocket next to a mobile phone in a case which had a magnetic closure on it, and the magnet had reversed the polarity of the compass needle, so that the north arrow pointed south.”
The phenomenon of reversed polarity has been widely publicised in mountaineering circles and people are advised to keep their compasses well away from mobile phones.
But there is concern at the growing use of magnetic closures in outdoor clothing.
Mountaineering Scotland, which represents hillwalkers, climbers and mountaineers north of the border, said popular outdoor brands are producing mitts and gloves with fold-back flaps using magnetic closures and there is a wide choice of outdoor jackets out there replacing Velcro with magnets hidden away in folds of the garment.
“Pockets, hoods, front fastenings, wrist closures – they’re all out there,” it said.
Ms Morning said: “Modern technology is great. The resources available now to keep us warm and safe in the mountains have never been better. But more joined-up thinking is needed between outdoor clothing manufacturers and mountain users to avoid potentially life-threatening consequences.
“My advice is to steer well clear of any garments utilising this latest trend of magnetic closures or you could end up with an expensive bill for replacing your compass or – worse – a life-threatening navigation error.”
Dave Taylot
15 February 2018Yep, Fortunately some of us know that in this soaking mess of a country, the sun never goes north.
Several years ago, I was out with my brother who (incidentally) has a Honours degree in Geography. We were lost. Out came the map and compass. My bro worked out where we where and set a bearing. Thankfully, before we set off I noticed where the sun was. His compass had been subjected to something that had caused the polarity to go 180 degrees out. East was west. Fortunately, I had a rather expensive Silva compass in my pocket and we got out of it using that.
Now, I use my phone to work out where I am. I wouldn't have ever recommended to anyone depending on a phone, but after this episode I am more confident in it than a compass. At least it knows where I and what direction I'm going in.
Josh B
15 February 2018It's a fair point you make Dave - if in doubt, get the phone out. I'm not one to rely on it, but it's a good soundboard to check against if there is an element of uncertainty.
Nigel Williams
15 February 2018Whilst clothing, belt buckles and drinking tube attachments are using magnets, The mobile phone is the real culprit or anything with a speaker in it, radios and sometimes cameras. Speakers have magnets in and it doesn’t matter whether the device is turned on or off or even if there is a battery in it. Whilst it is possible to reverse the needle back to normal which I have done with a phone before now we don’t really know how strongly it has re magnetised. Send it back to the manufacturer.
I have heard it said you can just use the white end of the needle for north once you realise what has happened, however this is not a good idea. The white end of the needle (Silva Mk 4) is about 1mm longer than the red end to counter the north end dipping. So with the desire of the white end to dip and it’s additional length and weight it will tend to catch on the floor of the capsule and tends not to settle reliably.
I have seen around 40 reversed compasses over the last 10 years and heard of many more as I do a lot of teaching of the subject. For decades we have had metal objects, GPS, head torches etc in close proximity to our compass and I never came a cross a reversed polarity compass.
Bob L
15 February 2018My suspicions immediately fall on the mobile phone he says the compass was stored next to. I've had a couple of compasses reverse polarity, and I don't have any magnetic catches. I did, however, have them close to the mobile phone. When we checked the magnetic field generated by the phone it was quite high - much higher than expected, probably due to the magnet in the speaker. Since then I've always maintained good separation between the two.
OldManOfTheHills
15 February 2018I have experienced the problem myself. For a bit I simply thought I had lost my marbles as well as my bearings. I never thought about what might have caused it so now a bit more clued up, but I just threw the deceitful device away rather than try and remagnetise it.
In scottish clag or blizards when i most needed it seeing any sign the sun is rare and I didnt dare rely on that for a sense check to enable me to confirm it was the "odd compass"
Jon
15 February 2018Dave, I have to ask why you would need a compass when the sun is shining? It's usually when the visibility is very poor (and the GPS device's batteries have failed!) that a compass is necessary. When visibility is reasonable a map and the lie of the land are enough for most situations. This used to be a very good thing, in the days before GPS, when navigating in places where a compass is unreliable due to iron ore deposits and so on.
Ian512
16 February 2018Remember, the use of a compass is only a part of the navigation process. The map provides you with much more information and if you are using it correctly you will be aware of your surroundings and should be able to spot if you are heading off in the wrong direction before much harm is done.
heidi
17 February 2018Agree with you Ian. Before I take a bearing I make a rough estimate of the direction I think I should be going. So hopefully should have an idea that if the compass says something totally different then something is wrong
Ian512
17 February 2018heidi - yes, I do the same, it's a great help. Also, like to see how accurately I can estimate the bearing for a bit of fun.