Where are the Murphys - Incident Log Report

Rapid Quick Links with a Crack in its Sleeve

With the permission of the German Alpine Club (DAV) Safety Commission, we were allowed to publish the following translated article, which was originally created in German on 15.06.2016. Many thanks to the German Alpine Club (DAV) and the team of DAV's Safety Commission.

"Damage to rapid quick links may occur undetected when tightening their sleeves!

Rapid quick links are frequently utilized in sport climbing – particularly in climbing gyms, though also at anchor points on especially popular and difficult routes in climbing gardens. After we were informed of cracks in rapid quick links by a concerned climbing gym operator, we took a closer look and found that 8mm rapid quick links are prone to small cracks when their sleeves are overtightened. This can reduce their breaking strength to values that are significantly below the required standard!

Size and Quality Differences

Under European Standard EN 12275, the minimum required strength for rapid quick links used in climbing and mountaineering is at least 25 kN in the main direction and at least 10kN in the transverse direction. When purchasing quick links, one should make sure that both the CE marking and the four-digit identification number are affixed to the product! This four-digit number indicates that a product conforms to the PPE (personal protective equipment) directives. Rapid quick links certified for mountaineering are available from specialist shops starting at around three Euros – while especially strong, corrosion-resistant products cost considerably more. Although there are significantly cheaper products available at hardware stores, these have not been tested and generally do not meet mountaineering standards. Since the greatest forces in the entire safety chain occur at the intermediate belay points, this is not an area where one should skimp!

    Rapid quick link with a crack in its sleeve
    Picture: DAV Safety Commission

Damage Profile and Test Results

The question of whether or not a crack will occur is dependent upon the thickness and shape of the end of the thread. Some sleeves cannot be overtightened (i.e., the sleeve lines up with the end of thread), others can be overtightened with the sleeve being cracked in the process, and yet others can be overtightened without the sleeve being cracked. A crack in the sleeve keeps pressure on the closing mechanism and thus reduces its strength. These cracks are usually very small and difficult to see. In the cracked rapide quick links that we tested (all new, 8mm thick, and from the same manufacturer), the breaking strength ranged between 17.9 and 36.2 kN.

Implications

On the basis of our test results, we recommend:

• ... when closing rapid quick links, make sure that the sleeve is not overtightened. The sleeve should not be screwed past the end of the thread.
• ... check rapid quick links for cracks in their sleeves, and immediately set them aside if a crack is detected.
• ... use only rapid quick links with a CE marking and identification number at anchor points."