Impact of Three Single-Step Decontamination Methods on Respirators and Medical Gowns

Area of Science:

• Materials Science
• Infectious Disease Control
• Biomedical Engineering

Background:

• The COVID-19 pandemic created critical shortages of disposable personal protective equipment (PPE), including N95 respirators and gowns.
• Decontamination methods were explored to reuse disposable PPE, but concerns remained about efficacy and material integrity.
• While some N95 respirator decontamination methods received emergency use authorization, none were approved for gowns.

Purpose of the Study:

• To evaluate the effectiveness and impact of different decontamination methods on N95 respirators and surgical/isolation gowns.
• To assess if decontamination processes compromise the protective performance and material integrity of PPE.
• To compare autoclave sterilization, gaseous ozone, and microwave-generated steam for PPE decontamination.

Main Methods:

• N95 respirators were decontaminated using autoclave sterilization and gaseous ozone; microwave-generated steam was also used for N95 respirators.
• Surgical and isolation gowns were decontaminated using autoclave sterilization and gaseous ozone.
• Decontaminated PPE was tested for filtration efficiency, pressure drop, tensile strength, and material integrity.

Main Results:

• N95 respirators exhibited significant deformation after decontamination, but filtration efficiency, pressure drop, and tensile strength remained largely unaffected.
• Surgical gowns maintained their protective levels post-decontamination, though sample size limited definitive conclusions.
• Autoclaving caused severe material failure in isolation gowns due to high heat, whereas gaseous ozone resulted in a lower failure rate.

Conclusions:

• Deformation of N95 respirators post-decontamination does not necessarily equate to loss of protective function; fit testing is essential.
• Gaseous ozone is a more suitable decontamination method for isolation gowns compared to autoclaving, preserving material integrity.
• Further research is needed to establish acceptable quality levels for decontaminated gowns.