On September 14, the city of San Francisco issued its own guidance apart from the state's gym/fitness center guidances. After months of being shuttered, the city's three climbing centers were told they needed to remain closed because the guidance included a specific call out:
At the current time, pending further developments, climbing walls are banned due to the difficulty with adequately disinfecting between each use.
Representatives of the three gyms were not consulted on the matter, nor were they furnished with any justification. City officials have not been open to discussion, despite the phraseology of the guidance.
Sources say that they appeared to be proud of their stringent requirement, despite zero backing for their rationale. Prior to the initial shutdown of California businesses, transmission of COVID19 was not known, but we now know that it spreads through aerosoled droplets and person-to-person contact, not surfaces.
The specific reason also does not take into effect to the existence of at least three independent studies showing that the virus is killed upon contact with climbing chalk - which covers climbing holds and is regularly reapplied through active use of the walls.