The UIAA – International Climbing and Mountaineering Federation – regularly receives questions related to safety topics. The UIAA Safety Commission, with support of other UIAA Commissions and experts, has commenced a series of articles answering common questions with the objective of making them available to the wider climbing community.

This first topic is:

A number of climbers put on sunscreen when at the crag, climbing or belaying. Is this a good idea and does it damage equipment?

UIAA SafeCom: What effects certain substances have on the performance of rope is an interesting topic. John McKently and collaborators have previous led discussions on this subject. Their research has strong practicality but is now a little dated and covers some standard everyday substances that ropes could be exposed to. Sunblock/cream was not one of the areas addressed. Furthermore, sunblock can vary by composition, and its nature can change on a fairly regular basis (such as newer formulations being reef-sensitive). McKently did find that pH seemed to be the worst offender of nylon.

Having said that, nylon products like ropes, slings and cords are the ones to be concerned about with respect to exposure to sunscreen and/or insect repellents. SafeCom does not envisage any reason why metal products would be attacked, with respect to any likely contact with a small amount of sunscreen.

For nylon used in climbing items, it is well known that some chemicals, like sulphuric acid – even in very small amounts and even as a vapour – can lead to climbing rope failure (sadly there have been accidents and fatalities due to this). And that whilst SafeCom doubts there is sulphuric acid in sunscreen, or other sprays and lotions (such as insect repellent), there might well be a chemical presence in some brands that does attack nylon. For instance it is known that certain types of insect repellent can damage plastics, and might be prone to attack nylon climbing equipment too.

Therefore, as would seem common sense, SafeCom recommends that climbers do their best not to get sunscreen or other lotions and sprays on any climbing gear, and especially not on nylon products. Sunscreen designed for lips needs to be safe to swallow in small quantities, therefore as a rough rule of thumb is probably not going to be aggressive enough to attack your rope.

SafeCom does not currently have the resources to investigate further, but would welcome research into the following suspicion: sunscreens that contain alcohol, or other solvents that evaporate, are probably more aggressive than those that are in effect zinc oxide-based.

Furthermore sunscreen can be very debilitating if entering ones eyes through perspiration, and then made worse by rubbing eyes, especially if hands still have suncream on them. Is is advisable to carry a handkerchief or glasses cloth for this purpose and to wash/cleanse hands after applying suncream.

To submit a question to be addressed by the UIAA Safety Commission please click here.