I can’t figure out how to quote you, @enjoytheride! Masks are now required in the indoor, but we’re all riding there because it’s cold/windy.
I don’t know if, scientifically, one unmasked rider with asymptomatic covid could infect another in a 90x200 indoor in the span of an hour, even if that indoor is not well ventilated. Honestly - probably not. But we have 3 trainers on property who spend all day in that ring, and 40 horses, so maybe the aerosols could accumulate over the course of the day if multiple clients (or trainers, or staff) were sick. It is stuffy enough in there that the mirrors will fog up on busy days.
In truth, the science of it doesn’t really matter to me. What matters to me is that the trainers have agreed this is their preference and what makes them feel safe at work, so I am happy to oblige them. It’s not that big a deal for me to wear a mask for my 40 min hack, and it’s worth it for my trainer’s peace of mind and sense of safety.