Abstract View
Healthcare Acquired Infections (HAIs), Coronavirus, and Filtration Efficiency
NIKKI SASHER, AAF Flanders
Abstract Number: 597
Working Group: Infectious Aerosols in the Age of COVID-19
Abstract
Air quality has profound health implications in all indoor environments where the U.S. population normally spends most of their time. Specifically, indoor air can expose humans to hazardous biological and chemical agents. The quality of indoor air is therefore a prominent public health concern that requires a clear understanding of the transmission processes for the development and implementation of targeted infection prevention and control measures. World-wide outbreaks of coronavirus-caused COVID-19 and severe acute respiratory syndrome (SARS), H5N1 bird flu, and H1N1 novel influenza have caused a substantial health impact to the population and have increased public concerns for the spread of viral disease. The global pandemic caused by the novel coronavirus SARS-CoV-2, which causes the disease known as COVID-19, has changed the world in ways no one could have imagined. There is much more to learn about this emerging global threat, however, there are some aspects of the virus that are known. The main route of transmission of the virus is thought to be through respiratory droplets expelled when sneezing, coughing, or even talking. Therefore, there is a strong desire to mitigate risk to the general population. With the goal in mind of evaluating coronavirus filtration efficiency if the transmission mode becomes aerosolized and into an HVAC system, AAF’s Biological Research Department launched a study utilizing a safe surrogate for the SARS-CoV-2 virus in order to evaluate the virus removal efficiency of several filters ranging in efficiency ratings of MERV 14-16. Air samples containing surrogate virus were collected upstream and downstream from the filters using aerosol test equipment such as Anderson Cascade Impactors and optical particle counters to be able to separate particles by size (approximately 0.3 to 10 microns). Then the samples were tested by quantitative reverse transcription polymerase chain reaction (RT-PCR) and a fluorometer to estimate mass. For each particle size, the particle size removal efficiency was calculated. The results showed that under the conditions of the study, filter efficiency for SARS-CoV-2 surrogate virus was comparable to filter efficiency using KCl particles (ASHRAE 52.2 standards). In addition, the efficiency of particle removal was similar across the methods used (optical particle counter, fluorometer or PCR).