Does a surgical helmet provide protection against aerosol transmitted disease?

Abstract

Background and purpose — The COVID-19 pandemic caused by infection with SARS-CoV-2 has led to a global shortage of personal protective equipment (PPE). Various alternatives to ordinary PPE have been suggested to reduce transmission, which is primarily through droplets and aero-sols. For many years orthopedic surgeons have been using surgical helmets as personal protection against blood-borne pathogens during arthroplasty surgery. We have investigated the possibility of using the Stryker Flyte surgical helmet as a respiratory protective device against airborne- and droplet- transmitted disease, since the helmet shares many features with powered air-purifying respirators.

Materials and methods — Using an aerosol particle generator, we determined the filtration capacity of the Stryker Flyte helmet by placing particle counters measuring the concentrations of 0.3, 0.5, and 5 μm particles inside and outside of the helmet.

Results — We found that the helmet has insufficient capacity for filtrating aerosol particles, and, for 0.3 μm sized particles, we even recorded an accumulation of particles inside the helmet.

Interpretation — We conclude that the Stryker Flyte surgical helmet should not be used as a respiratory protective device when there is a risk for exposure to aerosol containing SARS-CoV-2, the virus causing COVID-19, in accordance with the recommendation from the manufacturer