Cleaning a Bicycle Helmet
Summary: Clean your bike helmet as recommended by the manufacturer, or just use mild soap and water. Do not put your helmet in a dishwasher. We have COVID-19 advice further down this page for new or used helmets.
If you have no idea where your instructions are, what then?
Do not put your helmet in a dishwasherWe have a page up describing our dishwasher tests that will show you how it will degrade your helmet.
Cleaning ProductsThere are at least three spray products made specifically for helmets.
If you want to keep your helmet clean by using a liner, check out the Sanitete disposable liner from France. It probably would interfere with normal fitting pads, but it might be useful for the louse problem when swapping helmets. The cost is just under a US dollar. And you can check out the Esco head protector available at Misumi. We have less expensive options on our louse page, including surgical caps and painters' caps.
COVID-19First, do not put your helmet in a dishwasher or washing machine. We did a study on that and concluded that even dishwashers damage bike helmets.
The most frequent general advice for cleaning a helmet generally and for eliminating the COVID-19 virus is to wash with soap and water, then dry. CDC has this additional advice about mailed packages that may be relevant on their FAQ page as of March 31, 2020:
"Am I at risk for COVID-19 from a package or products shipping from China?
There is still a lot that is unknown about the newly emerged COVID-19 and how it spreads. Two other coronaviruses have emerged previously to cause severe illness in people (MERS-CoV and SARS-CoV). The virus that causes COVID-19 is more genetically related to SARS-CoV than MERS-CoV, but both are betacoronaviruses with their origins in bats. While we don't know for sure that this virus will behave the same way as SARS-CoV and MERS-CoV, we can use the information gained from both of these earlier coronaviruses to guide us. In general, because of poor survivability of these coronaviruses on surfaces, there is likely very low risk of spread from products or packaging that are shipped over a period of days or weeks at ambient temperatures. Coronaviruses are generally thought to be spread most often by respiratory droplets. Currently there is no evidence to support transmission of COVID-19 associated with imported goods and there have not been any cases of COVID-19 in the United States associated with imported goods. Information will be provided on the Coronavirus Disease 2019 (COVID-19) website as it becomes available."
In addition, testing has shown that the virus "was detectable in aerosols for up to three hours, up to four hours on copper, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel." If the helmet is wet the virus may live longer.
We tested the bleach solutions recommended to clean the virus off most surfaces (1/3 cup bleach to 1 gallon of water) for helmet damage. The mix is surprising strong, and just a sip burns the tongue and mouth enough to threaten real damage if you swallowed any. (Our tester spat it out immediately and rinsed.) Just a dip into that mix should kill the virus, but we wanted to set up a worst-case test to make sure it would not damage the helmet. Our test rig was a gray plastic receptacle commonly known as a trash can. Here is a photo of two helmets, black and white, in our test rig:
The helmets are held under the surface but not entirely submerged. We are using fresh heavy duty Clorox Performance Bleach, 7.55 per cent Sodium Hypochlorite. It came from Costco one month earlier. Since labs are closed, we are not able to crash test the helmets after the test as we did for our earlier study of cosmetics, sunscreens and hair products.
The ASTM and CPSC bicycle helmet standards require helmets to perform in impact tests after being immersed in ambient temperature "potable water" for a minimum of four hours. Adding a third of a cup of bleach to the gallon of water is not a radical change in that requirement, although the solution is strong.
You would not have to do this at home, but we immersed the two helmets in the water and bleach solution for 40 hours. That is ten times the length of time they are normally immersed by the test lab. We then washed them off and let them dry for three days. The older helmet was from 1998, and it suffered pad deteriortion, with the pads turning to dust, but that is typical of 20 year old helmets anyway. It was otherwise intact.
The newer helmet showed no effects.
Both helmets still had their original labels. Although we are not able to test the straps in a lab at this point, both straps resist strong pulls and seem as strong as ever. The buckles work well and seem unaffected. The rear stabilizer adjustment on the newer helmet still works.
We conclude that if you decide to use a water/bleach solution to speed up decontamination of a helmet that may have been exposed to COVID-19 you are not likely to damage the helmet. If you have more time, just putting the helmet on a shelf for more than three days will accomplish the same thing according to the CDC data. That's what we would recommend doing, even with a brand new helmet. The bleach could fade a new helmet's interior, so we would just quarantine it and wash it normally with warm water and mild soap before wearing as you would with any article of clothing.
There are many other chemicals that can eliminate COVID-19 quickly that we have not tested. Here is the Environmental Protection Agency's list of chemicals that meet EPA's criteria for use against SARS-CoV-2, the virus that causes COVID-19.
This page was revised on: September 28, 2020.