Equipment lifespan
A question I often get asked, as a thorough examiner of arboricultural equipment, is how long a particular piece of equipment lasts. It may, on the face of it, seem like a straightforward question and it is. But, as is often the case, it also has the potential to lead to a minefield if you make assumptions.
Before we get started I should probably explain that what we are talking about here is service life or lifespan, not wear and tear or damage. So if your gear is not damaged or worn out, how long can it potentially last?
Always follow manufacturers’ advice
The fundamentals are simple: you follow the advice of the company which made the item. So if they say it lasts for 5 years from the date of manufacture, then that’s how long it lasts. And some manufacturers are great at giving really clear advice. However, this does mean you have to be a bit more on the ball when you are buying stuff, because if your supplier has had it on their shelf for 5 years and the advice from the manufacturer is as above, then it has already effectively retired.
What’s it made from?
The next thing to think about is what the gear is made out of (e.g. metal, plastics, textiles etc.) because different materials all have the potential to have different lifespans. I say ‘potential’ because – sorry, ART lovers – ART textiles and metal can have the same 5-year service life. Yes, that’s right: your new Spiderjack 2.1 that you have saved all your pennies for will only last you 5 years from its first use, or to give you the ART wording:
‘If this equipment is used as intended the service life of metal elements under consideration of all manufacturing information is a maximum of 5 years after using for the first time. The maximum service life of textile elements (insofar as these exist) is 5 years.’
So for some gear it doesn’t matter what the components are made out of, their lifespan is the same, although this is the exception rather than the rule. Even ART seems to vary this rule as your Spiderjack 3 metalwork will last 10 years but the textiles, as far as they exist, only last 5 years.
Lantra Awards gives general guidance for its thorough examination course. However, it does give the caveat that you should always follow the manufacturer’s guidance. Lantra states that textile lifespan is 5 years from the first use (10 years from date of manufacture) and for metalwork it is when it wears out.
Service life
Some manufacturers allow service lives for equipment beyond those limits. For example, Petzl give the textile and plastic elements a 10-year lifespan from day of manufacture, with the date of manufacture indicated by the first 5 digits on the serial number – year and day number – although for some newer items there may be a letter present as well.
So, if you get an item the year Petzl make it, say a Petzl Sequoia harness, it could last you twice as long as your Teufelberger treeMOTION harness. Some manufacturers go even further, with Tree Austria harnesses having a 10-year in-service maximum life and 12 years from date of manufacture!
However, not all manufacturers give such straightforward guidance. Some only make vague statements about lifespan, such as Marlow’s ‘It is important that a rope is regularly inspected to ensure that it is undamaged and is still fit for service. The entire length of rope should be examined. The following are some of the points that should be checked. The degree to which any of the following may be allowed before the rope is retired will be dependent on the assumptions made when the rope and safety factors were determined.’ These are all good points, but they don’t give any guidance on lifespan and this is from the section on Marlow’s website for lifespans! When contacted, Marlow said that it gives a 10-year shelf-life for textiles, but once the rope is used it could give no guidance. This is fair I suppose, but it may be useful to put this information on the company’s website. Also, other manufacturers do manage to give guidance on service life once a rope is in use. It is important to stress that wear and tear or damage could render an item unfit for use at any time including before or on the first use.
Also, don’t assume that the guidance from Lantra Awards gives you the minimum lifespan of textiles or metalwork. We have already talked about ART’s 5-year lifespan for metal, but there are ropes such as Teufelberger’s OD (Ocean Dyneema®) that have an in-service lifespan of 2 years, or to quote:
‘The product‘s service life may be up to 2 years from the day the product was first taken out of the undamaged light-protected package, and the product must be retired after no later than 2 years of having been used. It is assumed that the product is taken out of the package at the time of the purchase. We recommend that you keep the original sales receipt which is the proof of purchase. The theoretically possible total product life (correct storage prior to first removal + period of use) is limited to 5 years from the date of manufacture.’
This is because the product is very sensitive to UV degradation according to the manufacturer.
Choosing wisely
This information can change how you look at gear. It has definitely put me off gear from companies that are vague or unclear about how their product will function in the wider world. It has also changed how I look at gear from a purchase point of view. As a recovering gear junkie I now think more carefully about a piece of gear at the point of purchase: will it get used, or will it get retired having only been out to play once or twice? It has also makes me check dates on gear when I purchase a new bit of equipment. It has only happened once, but I have been sent gear from a reputable supplier that had already passed its maximum service life, so it had to go straight in the bin. To be fair to the supplier, once they had checked with the manufacturer that I was correct, they replaced the item with one that had been manufactured that year. Or, to put it into context, if your new shiny treeMOTION harness was manufactured in 2013, it doesn’t matter if it is still in the bag and you only just got it: it retires this year however good it looks. However, a Petzl Sequoia harness manufactured in the same year still has potentially a 5-year service life.
Hopefully the key bits of information you will take away from this article are:
- Read and keep the technical data that comes with your kit. Not all kit lasts for the same period, whether that means how quickly it wears out or how long the manufacturer gives it as a lifespan.
- Know where the date is and check the date on kit when you purchase it, otherwise you could have disappointing news at your next thorough examination.
- And finally, it isn’t the thorough examiner’s fault when gear is retired through age. It is because the manufacturers, through the checks and balances they have to carry out, have deemed that those materials can only last that long once they are manufactured.
Thanks for reading and happy climbing.
Note: All information referenced in this article was accurate as of May/June 2018 and was taken directly from the relevant manufacturer’s website or the downloaded technical data sheets. Where these were not available the manufacturer was contacted directly and the information referenced from that personal communication. In the case of Lantra Awards it was taken from the 2015 thorough examination course handout, which is currently still in use on its courses. If information couldn’t be found, the manufacturer or item was not mentioned in this article.
Matthew Cooper
Matthew is Director and Principal Arboriculturist at Tree Research, Education and Environmental Services Ltd, Livingston, West Lothian.
Article taken form Issue 183 of The ARB Magazine. Members can view their copy here.