Tool tethering, how would you choose?
The last few years have seen a great number of tool tethering company's formed On the whole there seems to be a great deal of misunderstanding in the market place with a belief that any answer is better than none. As with everything to do with safety, providing something that is not the correct solution may lead to increased risk. This is where only a specific risk assessment will provide you with the correct answers.
HSE regulations state all of the ways that can be applied in the Work at Height Regulations but leave certain aspects down to an understanding of what is taking place. In particular tool tethering and break out forces, so as to ensure that the tool which is preventing injury to others does not also injure the user if dropped.
Break out force is the amount of force required so that the tether will break rather than restraining the item to the wearer.
The potential problems for this are quite high. Lanyards may well have a tool weight that they can sustain and it needs to be established if this has been calculated allowing the tool to fall the full length of the lanyard without releasing it or not. So a tool retention lanyard marked for use with tools up to 2.5 kg needs specification of how much force would detach the lanyard. Now apply a 4.5 kg lanyard and imagine this is a wrist attached lanyard with a length of 700 mm. Now try to imagine if you could stop that resultant falling force once it reaches its full length and add to it that you are working at height. If not there is only one direction you can go!
A risk assessment will provide you with the correct answer. The weight of the tool, the distance the lanyard can travel and then the resultant peak force that will be delivered back onto the wearer. If the resultant peak force for break out would pull the wearer from there position if they drop their tethered tool then you have supplied them an incorrect safety measure. This could then be taken further, if the break out force is way too high the lanyard and tool could then get caught up and act as a restraint in a fall, causing the workers body to be subjected to a loading at points not designed for injury prevention and could even be fatal.
Tool tethering can be a good option to increase safety but only if all of the forces and what is being used are understood. With ever increasing products on the market this can make selection very difficult, as so far there seems to be no real standard that can be applied. Whilst the Work at Height Regulations do cover why and what you have to do there is no real content that gives help to safe equipment choice.
Although the regulation does state that there should be competence for planning and supervision in relation to working at height. This covers many sections that are concerned with being able to conduct a risk assessment and would lead you to the correct conclusion. But how many are truly adopting this policy in the way in which it was written. The whole idea of risk assessment is to associate the hazards and risks and them formulate a method statement that limits those risks so that the worker will not be harmed. This can only be applied if the person conducting the risk assessment understands how the equipment acts.
For fall arrest this is fairly simple and there are specific EN numbers for each task. This is widely understood and linked with many case studies and quantifiable data. This is not the case with tool tethering so far it would appear, so choose carefully.