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Continuous update of new tree climbing products, equipment and tools

Petzl respond to Treetools position on the ZigZag

Saturday, July 19, 2014

Petzl has now found the causes of the potential appearance of such a crack. Technical improvements are already in progress. An updated communication will be given simultaneous worldwide release on 23rd July 2014. This communication will include a clear explanation of the causes of the potential of such cracks and a description of the actions which have been taken to prevent cracks forming in the future. (The 23 July 2014 PETZL ZIGZAG INFORMATION UPDATE is available now for download from the Petzl website).

Petzl confirm that a cracked link presents no risk to the user. However, as with any personal protective equipment (PPE), the presence of a crack requires immediate retirement of the device, which will be replaced under warranty. We are committed to continuous improvement of our products, and we act as soon as we detect a potential customer insatisfaction (sic).

Petzl confirm that the world wide ZIGZAG return rate for such a crack is below 2 /1000.

Petzl has always been transparent with our communication. User safety is always our first priority, and we will not hesitate to stop sales and recall products if we have any doubt.

If your ZIGZAG passes the normal Petzl PPE inspection procedure and the chain is free from cracks you can continue to use your ZIGZAG, but you will still need to carry out your regular thorough and pre-use checks as usual for all PPE.

Petzl decisions and recommendations for ZIGZAG and ZILLON devices:

  • A cracked link presents no additional immediate risk to the user. However, as with any personal protective equipment (PPE), the presence of such a crack requires immediate retirement of the device
  • Considering the very low rates of potentially cracked links, and taking into consideration that a cracked link presents no additional immediate risk to the user, only cracked devices will be replaced
  • The replacement of a cracked device will be carried out under warranty. The warranty for this defect has been extended to 10 years
  • Regularly inspect your device in accordance with the Petzl PPE checking procedure
  • In the unlikely event you find a cracked link, retire your device immediately and contact the Petzl distributor in your country

Posted by Richard Tregoweth Google+

Treetools pulls the plug on Petzl ZigZag sales

Friday, July 18, 2014

According to a Petzl representative, the worldwide return rate on the Petzl ZigZag is very low (1-2 units per 1000… and Petzl have sold tens of thousands around the world). The crack that appears in the top link represents NO risk to the user and all ‘problem’ ZigZags will be replaced under warranty.

All this may be true but Treetools cannot reconcile the fact that a PPE product is promoted and marketed as a ‘safe’ alternative to the humble Prussik when the product in question continues to fail in the field.

We say the Petzl ZigZag ‘fails in the field’ because Treetools return rate does not correlate with the Petzl’s worldwide figure of 1-2 per 1000 (Treetools return rate is much higher than Petzl’s).

Apparently the Petzl ZigZag problem is more prevalent in Australia and New Zealand?

Yes, kiwi climbers might be more aggressive in our tree climbing style but it is hard to believe the problem is regionally specific - we use the same climbing lines and hardware as everyone else in the world?

One possible reason for Treetools high return rate specifically is our proactive approach to the problem.

40% of Treetools returned ZigZags were due to us checking the ZigZag while in the field or in the shop – in these instances the owners of the device were oblivious to the problem until it was pointed out to them.

The high return rate of Petzl ZigZag through Treetools, let alone the obvious defect with the device itself, puts us in a compromised position.

Should Treetools continue to promote and sell a product we know to be deficient? (a cracked ZigZag would definitely not pass Petzl’z own gear inspection criteria).

The team at Treetools think the answer to this question is no.

Selling and promoting a PPE product, when there is a high likelihood for failure, goes against our basic instinct and the core philosophies of our business.

Therefore, as of today, Treetools will suspend sales of the Petzl ZigZag until the problem is resolved.

Posted by Richard Tregoweth Google+

Is vibration killing the Petzl ZigZag?

Monday, May 26, 2014

Experienced aerial arborists understand a climbing system must be fine-tuned for optimum performance.

To that end, a traditional knot-based configuration offers infinite variables for fine-tuning; friction cord type, diameter and length, sheath and core construction, choice of the friction hitch (knot), diameter of climbing line etc.

Unlike ropes, mechanical devices do not offer the same degree of tolerance. For example, if the device has a 12mm hole then it will not accommodate a 13mm rope.

And, most mechanical devices cannot be ‘dialled-in’ for optimal performance – when using such a device the only variable a tree climber has to work with is in the diameter and construction of the climbing line itself.

The appearance of cracks in six 2014 Petzl ZigZag worldwide (one from New Zealand) has got users questioning the device and how it works.

A common thread we are hearing at Treetools is the amount of vibration you get on descent when the Petzl ZigZag is combined with different climbing lines – some work perfectly well and others are virtually useless.

Anecdotal evidence suggests if the rope is too thin, that is outside of Petzl’s specification of 11.5mm diameter, you are bound to get severe vibration running through the device on descent.

But the vibration can also occur with climbing lines inside the Petzl spec, in particular, when using 16-strand ropes.

The knobbly sheath of the 16-strand line sets the Petzl ZigZag links into rapid motion not unlike the effect on a vehicle travelling over rutted corrugations on a metal road – and we all know the result of this kind of vibration on even the toughest of vehicles.

The cracked link on the Petzl ZigZag is at the very end of the ‘chain’ so, in theory at least, this link will receive the highest concentration of vibration. Perhaps, over a period of time, this is enough to fatigue the metal to cracking point?

This might also explain the randomness of the problem – the crack could be entirely dependent on the climbers’ configuration (choice of climbing line) and amount of climbing hours undertaken.

Posted by Richard Tregoweth Google+

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