There are some no brainers like don't throw your climbing rope next to car batteries in the back of your car. The effect of bug sprays containing Deet seem to be controversial. I have also heard a degreaser or citrus degreaser in particular can damage a rope. I try to keep my rope as clean as possible but is there anything I should keep away from my rope or climbing equipment in general? Please don't hesitate to state anything that you might think is so obvious it's not worth mentioning.


  1. Is there any substance that I could reasonably come into contact with that if my rope does contact the substance the rope should be retired immediately and unquestionably? Again, a car battery in the trunk seems like the first thing that comes to mind.

  2. Any reason to be concerned about things like hand-sanitizer or sun tan lotion?

  • Are we talking about climbing ropes or any type of miscellaneous rope, such as paracord for repairing tent lines?
    – berry120
    Commented Jun 5, 2012 at 15:50
  • Ropes, cords and webbing used for top-rope and lead climbing.
    – DJBunk
    Commented Jun 5, 2012 at 16:12
  • 4
    definitely keep them away from cats - they can shred a good climbing rope in no time!
    – Rory Alsop
    Commented Jun 6, 2012 at 8:01
  • 2
    Just to emphasize, Sicherheit und Risiko in Fels und Eis contains a nasty fatal case where a rope ripped during an abseil. Subsequent investigation showed that the rope had been stored next to car batteries and slowly dissolved inside out.
    – Maurits
    Commented Jun 10, 2012 at 12:13
  • The breaking strength of a climbing rope far exceeds the forces a falling climber exerts on it (e.g. 11mm rope 34kN break, 9kn factor 1 fall), so for a rope to break it is down to 1/4 its strength. The fact very few falls (probably less 10 recorded in history) are caused by chemically weakened rope failing (as opposed to mechanical damage) indicates chemical damage is either very obvious (rope not used) or not severe enough to materially affect the strength. (Not in any way suggest care is not required, just paranoia needs to be avoided.)
    – user5330
    Commented Dec 16, 2014 at 8:25

4 Answers 4


The following references from a few major rope manufacturers cover rope care thoroughly. Please see the bottom of this answer for a summary.

From Bluewater Ropes:

Avoid stepping on your rope. Beside the potential of cutting, stepping on a rope will grind dirt into the core and increase the possibility of internal abrasion.

Protect your rope from exposure to harsh chemicals. Do not allow your rope to come into contact with any compounds containing acids, alkalis, oxidizing agents or bleaching compounds. Be especially careful to avoid contact with battery acid or fumes. To help protect a rope from coming into contact with unidentified chemicals, always store and transport it in a rope bag.

Testing done indicates salt water, acetone, benzene, chloroform, freon, gasoline, kerosene, motor oil, mineral oil, paints and pine oil do not appreciably affect nylon and should not damage your rope. Laboratory tests performed have shown no appreciable damage done to nylon fibers by contact with insect repellents containing DEET (Test #0559).

Keep your rope clean. Dirt can shorten the life of your rope by increasing internal and external abrasion. It is a good idea to occasionally wash a rope to remove dirt and rock crystals. Put the rope in a pillowcase or washing bag and use a front loading machine with cold water only to prevent shrinkage. It is acceptable to use a mild soap to remove oil or grease but avoid harsh detergents. DO NOT USE BLEACH OR BLEACH SUBSTITUTES. Make sure to rinse thoroughly. Small amounts of fabric softener may be used to give better flexibility and a softer hand as a rope stiffens with use. Your rope should be air dried away from direct sunlight. It will not harm a rope to store it wet. Nylon is not affected by water and will not rot or mildew.

From Sterling Rope:

  1. What chemicals are bad for my rope? It is best to assume that all chemicals are bad for your rope. Do not expose your nylon or polyester ropes to chemicals. That said, much recent data has been collected regarding how substances affect rope life. Data available from Honeywell Corporation (makers of nylon 6, polyester and Spectra®) shows that nylon’s strength is not greatly affected by motor oil, mineral oil, salt water, Freon, gasoline, kerosene, benzene, chloroform, paints, pine oils, or insect repellents containing DEET. Chemicals that should be avoided at all costs are bleach and sulfuric acid. Still even with this reassurance it is best to protect your rope from any exposure to any acids or alkalis and to store your rope in a cool dry environment.

From the UIAA:

Notification Concerning the Marking of Ropes

Tests done by the UIAA Safety Commission and some rope manufacturers have shown that marking ropes with liquids such as those provided by felt-tipped pens can damage them; even with those markers, sold specifically for marking ropes. The test results have shown a decrease of up to 50% of the rope strength, more correctly: of the energy absorption capacity of the rope (expressed by the number of falls in the standard test method in accordance with the UIAA Standard101). Therefore the UIAA Safety Commission warns against marking a rope with any substance that has not been specifically approved by the rope manufacturer of that rope.

Also from the UIAA:

Conclusion: If you want to survive whilst climbing and mountaineering, please do not fall so that your rope comes tight over a sharp rock edge, and do not touch the rope with any acid!

See also the guide from Mammut.

Another reference that is too lengthy is from Black Diamond. It discusses the effect of urine on rope strength, which is surprisingly quite bad. (This article is no longer available, however this article references the preliminary testing done by Black Diamond.)

To Summarize

Avoid these things:

  • Sharp edges, especially under load
  • Acids & Alkalis Sulfuric acid, or battery acid, being a primary concern. Also urine, which contains uric acid among other things, is notably damaging, but only with extended exposure.
  • Bleach & other oxidizing agents
  • Extended UV exposure
  • Solvent-based markers or pens
  • Ground-in dirt or rock dust Keep rope as clean as possible and as is practical, and wash it appropriately when needed.
  • Letting wet rope freeze Temporarily weakens the rope while frozen, but may be unavoidable for ice climbers in certain conditions.
  • High heat This one's probably obvious, but nylon, comprising all dynamic ropes, will melt at 428°F (220°C). So campfire, stove, oven, dryer,... with high friction (nylon to nylon is really bad) being the most likely source to damage your rope.

To answer the question about hand sanitizer and sunscreen: There seems to be no specific testing of these substances on climbing rope. Use your judgement, but I see no reason to think that hand sanitizer or sunscreen would pose any threat to rope if it does not contain any of the above-mentioned damaging substances. Hand-sanitizer typically contains alcohol, moisturizers, and fragrance. Sunscreen typically contains a UV-inhibiter like titanium dioxide or zinc oxide, moisturizers, and fragrance. None of these substances is listed as harmful to nylon or climbing rope by rope manufactures or the UIAA.

  • 5
    +1 excellent sourcing of information from proper authorities.
    – DavidR
    Commented Feb 12, 2013 at 15:46
  • @DavidR - Thanks. There was another online resource that was more all-encompassing that I've referenced before when I had to train some people on rope, but I couldn't remember where it is. If I find it I'll edit this to be a little more concise. It really covers all the same stuff though.
    – montane
    Commented Feb 27, 2013 at 7:18
  • 2
    "It is best to assume that all chemicals are bad for your rope." But... air is made of chemicals.
    – endolith
    Commented Jul 2, 2018 at 14:28

Plainly speaking, it makes sense to keep your rope away from any chemicals at all - battery acid, grease, oil, bleach, etc. Same goes for any objects that might harm it, chemically (car batteries) or physically (anything sharp or jagged that may dig in.) Take care of it, keep it dry, well coiled and well away from anything that might harm it.

Yes, it may be true that certain chemicals may not harm it, and theoretically you may be able to leave it secured next to objects that would otherwise harm it, but there's just no need for the risk, especially if we're talking about climbing ropes. If you're in the slightest bit worried as to whether something might harm it, don't take the risk.


A concise summary of no-nos for nylon rope and webbing:

  • Strong acids and alkalis, particularly battery acid and muriatic acids, and chlorine bleach. Black Diamond replicated a harness failure where the critical stitching pulled apart under finger tension after immersion in weak battery acid.

  • Prolonged UV exposure (we're looking at practical climbing usage up to hundreds of days, so the worry about drying washed rope outdoors is a bit loony).

  • Heat above 300°F/150°C. (way above boiling water temp)

Contrary to logic: NOT so much issues with solvents, even DEET. Xylene however may be bad.

From http://www.sterlingrope.com/2000/climbing/prodev/tech.htm It is okay to use the hot water setting on your clothes washer to wash a rope. During the manufacture of the rope it is exposed to 180 degree steam. Damage to nylon does not occur until it has been exposed to 300 degrees for over 5 hours. Even if your washing machine brings the water to full boil it is not possible to reach 300 degrees. It is okay to use a non-bleach detergent.

Last, LOL, from MSR circa 1969: (referencing their sale of perlon ropes, which could be purchased as:) Unprocessed Rope

You can also process your own rope by boiling it for 40 minutes, using Rit dyes in your own color combination. Unprocessed white rope, 0.11/ft. Allow for 15% shrinkage. The processing is very simple, and is standard practice in the nylon industry.
Ref: Handbook of Textile Fibers, Part 2, P. 268 and 294, by Cook (Merrow Publishing Co., England).

MSR also gave advice re: reboiling to regain dynamic properties lost in a long fall!


In addition to @manoftheson answer, I would recommend to have a look at Annex J of IRATA International Code of Practice (ICOP) (title: Resistance to chemicals and other properties of some of the man-made fibres used in the manufacture of rope access equipment). Il lists various chemicals, and gives their effects on various fibre types (Polyamide is the fibre which climbing ropes are made of, HPPE is known as Dyneema…)

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.