Thread by @CorsIAQ

1/ Simple answer = very little for aerosol particles but possibly (in some cases) dispersion that reduces close contact dose. But depending on flow conditions, there can be a low pressure zone on the downstream side that leads to some accumulation of particles.

https://twitter.com/duncan3ross/status/1388465599941066754

2/ The risk of people letting their guards down thinking that barriers are somehow effective for aerosol particles is much greater than any benefit, IMHO. Technical answer next.

3/ Is there a benefit in terms of far field exposure? Very minimal. Here's why. Indoor aerosol particle decay rates (k) to (integrated) indoor surfaces range from approx 0.2 to 10/hr for 0.3 to 10 um particles, respectively (higher for larger diameter particles).

4/ k = vd x (A/V). vd is a deposition velocity, which is a function of particle diam, mixing conditions in bulk air, friction velocity near surface, and more. A = surface area. V = volume of interior space.

5/ Assuming that the barriers do not affect volume or deposition velocity (they might affect mixing and therefore could affect vd to some extent), then the key parameter is surface area, A.

6/ It does not appear to me that these barriers constitute more than a few % of the total surface area in the space (including walls, floor, ceiling, furnishings, & people when present) and would therefore lower particle decay rates by a tiny amount.

7/ In that context, it would probably be more effective to put patches of carpet on walls or fleecy materials hung from the ceiling to increase particle decay rate to materials with large surface areas (which I am not advocating).

8/ I am still not a fan of going to indoor restaurants right now because of the need to remove mask & because some (many?) will not be fully vaccinated. But the way to substantially reduce COVID-19 infection is not with barriers that (on average) have a minimal (if any) effect.

9/ The way to do it is to GET FULLY VACCINATED, wear a mask when not eating, minimize time in space (take out best) & for restaurants to increase ventilation & use one or more of: advanced central filtration, HEPA filtration systems, appropriate upper-room UVGI.