Study Showing Chalk Reduces Virus By 99% Now Peer Reviewed

New Study: Chalk Kills 99% of Coronavirus
Photo courtesy of Chalk Cartel

Last July, when the Association of British Climbing Walls (ABC) reported on early findings from a De Montfort University Leicester (DMU) study on the potential impact of climbing chalk powder on coronavirus transmission, the news quickly spread across climbing media. Climbing Business Journal, Gym Climber, Gripped, Climbing and the British Mountaineering Council, for instance, all published articles which discussed the findings (as well as the results of a Colorado University Anschutz study on Friction Labs’ Secret Stuff liquid chalk). However, one major limitation of the early findings from the DMU study was that it was not yet peer reviewed or publicly available. Now, according to a recent update on the ABC website, “The research carried out last year is now fully peer reviewed and the version of record is now live:”

According to the published study results, the DMU study tested the infectivity of a model human coronavirus for SARS‐CoV‐2 (HCoV‐OC43) in the presence of climbing chalk powders on a dry plastic surface. The chalk powders tested in the study were magnesium carbonate, calcium carbonate and a blended chalk, and infectivity was monitored at various time intervals over the course of one hour. Controls without chalk or the virus were also tested. As summarized by the ABC, “The results indicated that the amount of infectious virus was reduced by around 99% immediately upon contact with the chalky surfaces. By comparison, the control test where no chalk dust was present, showed only a slight decline in infectious virus over these time periods.”

Trango Holds Pardners


“This suggests that coronaviruses such as HCoV‐OC43 or SARS‐CoV‐2 are likely inactivated by climbing chalk, limiting the risk of potential fomite transmission. Further research into the stability of SARS‐CoV‐2 in climbing chalk would enhance our understanding of COVID‐19 transmission risks,” concluded the researchers in the published study results. The researchers leading the DMU study were Dr. Katie Laird (Head of the Infectious Disease Research Group), Dr. Maitreyi Shivkumar (Virologist) and Dr. Lucy Owen (Postdoctoral Researcher).

Even with the study now published and peer reviewed, the Climbing Business Journal encourages readers to note that the positive results do not suggest climbing chalk is a magic bullet for climbing facilities. Climbing gym operators should continue to apply recommended safety measures since aerosol transmission of COVID-19 is still possible and all studies have limitations. Still, the results are a positive sign for the industry. Alongside other factors such as safety measures and well-ventilated buildings, the presence of climbing chalk may be another factor contributing to the fact that, according to a Climbing Wall Association press release, “in 2020 there were zero confirmed COVID-19 outbreaks among the estimated 10 million visits to climbing gyms in North America.”

The full peer reviewed study can be accessed here, and stay tuned to CBJ for more industry updates.

Harness Consulting