Ten manufacturers have recalled from sale climbing kits for via ferrata mountain routes due to safety problems, says the Alpine Club of Switzerland, which issued a warning to climbers on Tuesday to check their gear.

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“Many climbing kits have considerable deficiencies and may break in a fall,” the club said in a German-language statement on its wesbite.

The kits, some of which are made by Swiss companies such as Mammut,  enable climbers and hikers to follow steep alpine routes by using slings to attach themselves to steel cables fixed to rock faces.

The kits are designed to offer climbers “protection” in case of a fall.

But certain models with rope brakes or “rope friction based shock absorbers” have been recalled to eliminate any risks.

The recalls follow testing and a list of potentially faulty equipment compiled by the German Alpine Club in the wake of a fatal climbing accident in the Tyrolian Alps in Austria last August.

“it was found that climbing sets with friction brakes from different manufacturers have some serious shortcomings and may not withstand a fall,” the Alpine Club of Switzerland said.

“Serious injury or death can result.”

Other via ferrata kits were recalled last fall after testing also found that “carabiner arms made from elasticated webbings were too weak”, according to Swiss manufacturer Mammut.

The German and Swiss alpine clubs have increased their requirements for via ferrata kits in a bid to improve safety.

Experts say that the maximum service life for via ferrata equipment is up to seven years when used only one or two times a year.

The lifespan drops to three years if the equipment is used several times a month, and to just six months if it is used daily.

Mammut provides a good explanation of how via ferrata kits or sets work on its website.

Via ferrata was popularized by Austrians in the Italian Dolomites during the First World War as a way of moving troops around.

In Switzerland, via ferrata or Klettersteig have only emerged in the past 20 years but the number of listed routes has increased to more than 150, including those along gorges and on high Alpine peaks.