While we are hesitant to quantify a safety level for our studios, a group from MIT did put together a theoretical model to calculate safe exposure times and occupancy levels for indoor spaces. By adjusting room specifications, ventilation and filtration rates, face-mask usage, respiratory activities, and risk tolerance, this tool can be used to measure how effective your mitigation efforts are against indoor airborne COVID-19 transmission in your space.
Based on our inputs, guests at our studios are adequately protected from contracting the virus through airborne transmission from an infected guest. Our studios are 1400 square feet, with 12 foot ceilings, Mechanical Ventilation with Merv 13 filters, Moderate Circulation, 40% relative humidity, with socially distant tables. Our guests communicate at the Talking (whisper) level, are required to wear face coverings at all times, and we ask any risky and symptomatic guests to return at another date. We assume course cotton masks, and that fit compliance is 75%.
Given these inputs, strengthened by our socially distant table setup, 38 people would be safe in the studio indefinitely (our temporary studio capacity is well below this number). Without our socially distant tables, up to 25 people would be safe (from airborne transmission from an infected guest) in our studio for over 2 hours. Lastly, the transient nature of our guests would only increase this protection.
Obviously, no one can predict with certainty any level of protection in any facility. But at least tools like these may be helpful to those looking to compare, or begin to quantify levels of protection. Please apply your best personal judgement to these predictions.
Check the safety level of your own space by putting your inputs in to the model here: COVID-19 Indoor Safety Guideline