UNbrella provides indoor table-side ventilation via large slow-moving (quiet) fan and internal F-UV light to sterilize exhaust in real-time.
CDC guidelines promote safe indoor mask wearing until seating and dining, but we know COVID is very likely already airborne (aerosol). Rooms full of people talking and eating are therefore unsafe, even beyond the 6-ft ballistic range. With UNbrella, patrons can wear a mask on the way to the table, but then relax and enjoy dinner within a safe negative-pressure localized area with friends. More important than intra-group spreading is inter-group spreading between tables within a public setting. UNbrella may be able to prevent both, while also very visibly (and stylishly!) reassuring patrons of the effect.
Early prototypes show a simple box-fan moves enough air to work well (smoke and bubbles demonstrate the effect). Using quick models we can test which blade size and speed will successfully move enough air volume to contain both ballistic and aerosol droplets. The umbrella format allows for large blades that can move high air volume at low speed, thus eliminating the noise nuisance and liability of fast-spinning blades. The table-side UNbrella optimizes the first rule of ventilation physics by limiting distance between output and input. The Far-UV light is a known technology that sterilizes the exhaust air safely (compared to UV-C which is harmful to humans) quickly enough for real-time sterilized circulation through the UNBrella chimney. Relatively cheap to prototype and iterate, this solution could be made locally by the many active metal-working shops within the city.
We know umbrellas work for seated dining, but we never had a reason to bring them indoors before! Therefore general dimensions of height and diameter are known and applicable. UNbrella will be free-standing and powered by simple DC electrical. Sheet-metal formed steel base and tubing, along with formed hood could all be achieved with local manufacturing. A simple mesh screen sits below the fan, made of non-woven recycled PET sheet (black color allows for recycled content). Non-visible and therefore simple wood or metal construction fan blades could also be manufactured locally, with standard fan motor and F-UV bulbs likely sourced as drop-in components (though motor / bulb housing would need custom fabrication, again possibly locally). The large formed hood could be colored or anodized according to decor. UNbrella would be a one-time investment per table or for every 4 patrons of $150 - $200 each. UNbrella could allow participating establishments to reopen.
Research and experimentation will be done if selected to proceed.
UNbrella specifically targets the time spent eating, which is a glaring hole within the current plan: "When dining out at a food service establishment or bar, customers can take off their masks while seated, but must now put masks back on whenever interacting with staff (ordering food, talking to servers)". During eating, UNbrella helps contain ballistic and aerosol contamination.