Surgical helmets can be converted into efficient disinfectable powered air-purifying respirators.

BACKGROUND: Filtering facepiece respirators often fail to provide sufficient protection due to a poor fit. Powered air-purifying respirators (PAPRs) are not designed for healthcare personnel, and are challenging to disinfect. Surgical helmets (SH) are available in many United States hospitals but do not provide respiratory protection. Several modifications to SH have been suggested, but none are sufficiently compliant with safety and efficiency standards. The purpose of this investigation was the development of a filter adaptor, which converts SHs into efficient, safe, and disinfectable PAPRs. METHODS: Four critical features were investigated close to regulatory requirements: total inward leakage of particles, CO2 concentrations, intra-helmet differential pressure, and automated disinfection. RESULTS: The average total inward leakage in the 2 independent tests were 0.005% and 0.01%. CO2 concentrations were lower than in the original SH. The modification generates a positive differential pressure. The filter's performance was not compromised after 50 cycles in a sterilization machine. DISCUSSION: The modified SH provides several hundred times better protection than FFP-3 masks. CONCLUSIONS: Surgical helmets can be modified into safe, efficient, and disinfectable PAPRs, suitable for HCP and the operating room in particular. They can play a role in the preparedness for upcoming events requiring efficient respiratory protection.

Utilizing Zirconium MOF-functionalized Fiber Substrates Prepared by Molecular Layer Deposition for Toxic Gas Capture and Chemical Warfare Agent Degradation.

Metal-organic frameworks (MOFs) are a class of porous organic-inorganic solids extensively explored for numerous applications owing to their catalytic activity and high surface area. In this work MOF thin films deposited in a one-step, molecular layer deposition (MLD), an all-gas-phase process, on glass wool fibers are characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and their capabilities towards toxic industrial chemical (TIC) capture and chemical warfare agents (CWA) degradation are investigated. It is shown that despite low volume of the active material used, MOFs thin films are capable of removal of harmful gaseous chemicals from air stream and CWA from neutral aqueous environment. The results confirm that the MLD-deposited MOF thin films, amorphous and crystalline, are suitable materials for use in air filtration, decontamination, and physical protection against CWA and TIC.