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Air filtration. More important for Restaurants than ever before!
The Covid-19 pandemic has crippled economies worldwide and brought entire industries to a screeching halt. The restaurant industry has been hit particularly hard by shutdown measures enacted to fight the spread of the virus with the National Restaurant Association reporting that 3 million jobs have been lost since March 1. In addition, one in five restaurants in the US could close permanently due to the pandemic, according to an estimate from the investment banking group UBS.
As restaurants, music venues, and other businesses where patrons interact in close proximity grapple with how to safely return to operation, weighing options like reduced capacity and increased spacing of tables, there are signs that redesigning our spaces and the way we ventilate them could work as an additional safety measure.
An interesting case out of Guangzhou, China examines the role that an air conditioner might have played in the spread of the coronavirus. In January, nine people from three different families became sick after eating in the same windowless restaurant although they were sitting at different tables, beyond the distance the droplets known to carry the coronavirus are thought to travel. At first, this is just frightening. Yet, none of the 73 other diners at the restaurant or the eight staff members were infected.
Researchers believe that an air conditioning unit may have blown viral droplets from an asymptomatic carrier at one table further than they normally would have traveled, ultimately infecting the other patrons.
It’s a scary thought indeed, especially as we try to take comfort in the fact that keeping a safe distance from others will help protect us from infection. There is a knee jerk reaction to eliminate the use of air conditioning or heating systems altogether to prevent such a scenario, however, there may be other, more useful, ideas to take away from the case. We can see in this case how a poorly functioning system was detrimental. Could a well-designed one be beneficial? This is the discussion now playing out among scientists and the media at large.
For years ventilation systems have been designed and implemented with cost and energy efficiency as the top priority. However, in the age of coronavirus, there is mounting evidence that designing air circulation for purification first might play a helpful role in reducing the number of infected particles in the air, especially for high volume or high turnover spaces like restaurants, theatres and music halls.
As we noted in a recent blog post, research suggests that because of the way that HEPA filters (High-Efficiency Particulate Air filters, common in HVAC systems today) work, they likely remove some, if not many, of the virus-infected particles from the air in circulation. It’s widely reported that HEPA filters do not capture particles smaller than 0.3 microns in diameter (the virus that causes Covid-19 is about 0.125 microns in diameter) but a recent article from Wirecutter, the NY Times product review website, contests this view, citing a detailed NASA study that shows HEPA filters are extremely efficient at “capturing ultrafine particles below the 0.3-micron HEPA test standard.” The article points out that the issue is not necessarily whether the filter can trap these particles (again, citing the NASA study it states that such a filter certainly would), but whether the particles are ever reaching the filter at all.
This point underscores the need for proper air circulation, and in light of our current situation, air circulation designed with purification as a top priority. Following the logic laid out in the Wirecutter piece, if we can better filter the air around us, adjusting systems to make sure air passes through these filters and passes through more frequently, we may be able to reduce the risk of airborne transmission in public and private spaces alike.
There are a lot of variables at play here, since the possibility and extent of airborne transmission of the virus is still being debated. Also, every space and system is different, and businesses will require custom solutions to fit their individual needs as they work to find a safe and workable way to get back up and running.
While air sanitizers and purification systems alone will not fully protect us from Covid-19, there is growing evidence that such systems can play a valuable part in an overall defense strategy. This is on top of the already proven benefits of proper air filtration, like the elimination of pollutants, mold, E.Coli, Staph, and other bacteria. But as the Wirecutter piece notes – it really comes down to proper circulation. If air is stagnant in a room or not reaching these filters, well that is no help at all, and might even make the room more dangerous.
Let’s fix that. Give us a call today to discuss how we can help your business return to safe operation as soon as possible.