It is becoming clearer and clearer that a primary mode of transmission for covid is airborne transmission. To protect against this, there are several things that would need to work in conjunction.
- Mask – to control the virus at source
- Ventilation - to clear out the air, and reduce the build up of virus laden aerosol particles
- Air Filteration - to clean the air in a room where huge changes in ventilation are not feasible and otherwise also.
Here’s a wired article on air purifiers: https://www.wired.com/story/could-a-janky-jury-rigged-air-purifier-help-fight-covid-19/
Air purifiers are expensive. The challenge is to design a low cost air purifier system that is mobile and can be easily put in a room, classroom, restaurant/eatery, and other spaces. Production and maintenance cost, ease of assembly, easy availability of materials on the market, low noise, portability would all be important criterion that will jostle for attention. Getting appropriate parameters for flow rates, filtration efficiency, relative to room size and occupancy would be important.
Basically, throwing this out as a design challenge if someone wants to take that up. Ventilation and filtration are now being recognised as important risk mitigation tools in the fight against COVID. Cheap, portable, accessible air filtration systems would also help with a host of other respiratory illnesses that plague folks in India. The need for this will not subside any time soon.