Why cleaning the invisible in restaurants is important during COVID-19: A case study of indoor air quality of an open-kitchen restaurant.

During the COVID-19 pandemic, restaurant sanitation and disinfection have become more important than ever although customers can hardly check visually. The most recent research argues that one invisible element leaving people vulnerable to the health effects of COVID-19 is particulate matter (PM), micron-sized particles known to cause acute or chronic respiratory illnesses, including lung cancer. While research shows PM is emitted from cooking, this study examines indoor PM pollution of an open-kitchen full-service chain restaurant, where commercial cooking occurs in the dining room, as a case study. The results of a week-long field test showed offensively harmful levels of PM and PM, far beyond US EPA and WHO standards, while ambient outdoor PM associated with the sample restaurant was safe. The study reveals that working or frequently dining in an open-kitchen restaurant where grilling or frying takes place is likely to cause respiratory health problems and elevate susceptibility to COVID-19 unless surveillance and preventative measures are taken. Based on our findings, implications and recommendations for the industry are provided.