After getting a question in the BIDA Facebook group, I was curious what mask policies contra dances are using. I looked at the dances marked as active on trycontra.com and checked their websites for mask requirements (sheet).

Of the 56 dances that have resumed, 31 (55%) require masks. Of those 31:

• 2 (6%) require surgical or better.
• 4 (13%) require a surgical + cloth or better.
• 4 (13%) require high-filtration masks (N95, KN95, KF94, etc)

Now that high-filtration masks are widely available, it does seem like a weird compromise to require masking but allow low-filtration options like cloth or surgical, especially when I haven't seen anyone wearing a P100. Specifically:

• Most of society is no longer requiring masks: bars, nightclubs, workplaces, transit, etc. In MA, one of the more cautious states on this issue, the state requires masks only in healthcare, paratransit, shelters, and jails.

• This means that the reason to require masks at dances is to allow people to attend for which it would otherwise be too risky.

• A group wearing surgical masks poses a risk to individuals (wearing the mask of their choice) that is roughly (per microcovid) 1/4 as risky as if the group were fully unmasked.

• An individual wearing a P100 is at ($16) (again, per microcovid) about 1/7 the risk of one wearing a high-filtration mask.

This means that if a group switches from masks-required to masks-optional and more cautious individuals switch to P100s, risk to those individuals very likely goes down.

Which then has me wondering: why do we see people saying that dances need to require masks, but not wearing P100s? Some guesses:

• People have adjusted to high-filtration masks now being available, but not to the availability of P100s.

• The P100 masks are more expensive up front. On the other hand, the part you wear lasts years, the replacement filters are ~$6/pair, and a filter pair lasts much longer than a disposable high-filtration mask, so the cost should be similar or lower over time. I also suspect that in most communities people who prefer dancing without a mask would be willing to cover the cost of P100s for people who need them if we could sort out a good way to do this?

• People may think P100s are less comfortable. My experience is that they are a bit more comfortable: slightly more pressure on the face but more spread out, and much less resistance to breathing.

• They have vents. This is an issue in places that require masks, since masks with vents are usually prohibited. Microcovid estimates that they provide a small amount of filtration on exhaust, about the same as a well-fitting cloth mask and about 3/4 as much as a surgical mask. I think they probably shouldn't be prohibited unless you're also disallowing cloth masks? This is also not an issue if masks are optional.

• They look weird. That, I will definitely grant, but I don't think that is enough of a reason to require everyone else to wear masks? And, of course, a dance full of masked people would have looked pretty weird in January 2020.

Overall, I think a policy of optional masks and subsidized P100s would be much better than just "masks required" (currently the most common thing for dances to do). I think it's likely also better than requiring high-filtration masks for everyone, but I'm less confident there.