Hillwalkers warned over potentially disastrous navigational errors caused by their bras

Hillwalkers wearing certain types of bras could end up making potentially fatal navigational mistakes, experts have warned. Outdoor enthusiasts risk making errors because items they wear or carry – including underwired bras – can stop compasses from working, the Mountaineering Council of Scotland said.

The group, who represent 11,300 climbers and walkers, said incidents where compasses were affected by reverse polarity were on the rise. They claimed magnets in mobile phones and GPS devices, metal car keys and bra wires could affect compass needles.



The council’s safety officer Heather Morning highlighted the issue. She said needles could be switched from point north to south, sending people in the wrong direction while trying to navigate off a hill or mountain in bad weather. Heather herself has experienced reverse polarity on three occasions in the past three months.

She said: “It’s a fact. Magnetic fields exist around many items we commonly carry with us on the hill– mobiles, avalanche transceivers, radios, personal locator beacons, GPS, cameras, car keys, small magnets on belt fastenings and underwired bras. The compass needle may be very briefly, partially or totally reversed when close to one of the above. The catalyst for a substantial number of mountain rescue call-outs in the UK is either directly or partially a result of a navigation error.”