The outbreak of SARS-CoV-2 has made us all think critically about
hospital indoor air quality and the approaches to remove,
dilute, and disinfect pathogenic organisms from the hospital
environment. While specific aspects of the coronavirus
infectivity, spread, and routes of transmission are still under
rigorous investigation, it seems that a recollection of
knowledge from the literature can provide useful lessons to cope
with this new situation. As a result, a systematic literature
review was conducted on the safety of air filtration and air
recirculation in healthcare premises. This review targeted a
wide range of evidence from codes and regulations, to
peer-reviewed publications, and best practice standards. The
literature search resulted in 394 publications, of which 109
documents were included in the final review. Overall, even
though solid evidence to support current practice is very
scarce, proper filtration remains one important approach to
maintain the cleanliness of indoor air in hospitals. Given the
rather large physical footprint of the filtration system, a
range of short-term and long-term solutions from the literature
are collected. Nonetheless, there is a need for a rigorous and
feasible line of research in the area of air filtration and
recirculation in healthcare facilities. Such efforts can enhance
the performance of healthcare facilities under normal conditions
or during a pandemic. Past innovations can be adopted for the
new outbreak at low-to-minimal cost.