Risk awareness during operation of analytical flow cytometers and implications throughout the COVID-19 pandemic. (Special Issue:SRLS in A Global Pandemic Environment: Lessons Learned from SARS-COV-2.)

The COVID-19 pandemic has brought biosafety to the forefront of many life sciences The outbreak has compelled research institutions to re-evaluate biosafety practices and potential at-risk areas within research laboratories and more specifically within Shared Resource Laboratories (SRLs) In flow cytometry facilities, biological safety assessment encompasses known hazards based on the biological sample and associated risk group, as well as potential or unknown hazards, such as aerosol generation and instrument failure modes Cell sorting procedures undergo clearly defined biological safety assessments and adhere to well-established biosafety guidelines that help to protect SRL staff and users against aerosol exposure Conversely, benchtop analyzers are considered low risk due to their low sample pressure and enclosed fluidic systems, although there is little empirical evidence to support this assumption of low risk To investigate this, we evaluated several regions on analyzers using the Cyclex-d microsphere assay, a recently established method for cell sorter aerosol containment testing We found that aerosol and/or droplet hazards were detected on all benchtop analyzers predominantly during operation in failure modes These results indicate that benchtop analytical cytometers present a more complicated set of risks than are commonly appreciated