Study urges climbers to stay clipped to steel cables in storms

Climbers on via ferratas should remain attached to the steel cable during thunderstorms, research involving the Tyrol Mountain Rescue Service has found, ORF reported.

The steel cable can act as a lightning conductor, while unclipping creates a risk of falling from the wall. Researchers tested the two risks using simulated lightning at Graz University of Technology.

The findings recommend staying attached during a storm. Climbers should keep their legs together to reduce possible step voltage and keep their hands away from the steel cable. Metal equipment should not touch the ground.

Plastic safety ropes carried little energy in the tests and therefore did not pose a significant risk, said Markus Isser, Tyrol Mountain Rescue’s medical training director. Carabiners attached to a climbing harness also did not create an additional risk as long as they did not touch the ground.

Climbers should leave the via ferrata before a storm if possible. If they are caught by one, they should follow the 30-second rule: action should be taken when the interval between lightning and thunder falls below 30 seconds. Lightning from a seemingly clear sky can also precede a storm.

Isser advised climbers to move away from ridges and exposed positions, make themselves as small as possible and sit on their rucksack with their feet together. They should keep at least 10 metres from trees, elevated points and other people. Sharp objects, including carbon poles, should be laid down rather than stood upright.

The research involved Tyrol Mountain Rescue, researchers from the Medical University of Innsbruck and lightning specialist Stephan Pack of Graz University of Technology. The tests were conducted in Graz using Tesla coils to simulate lightning.