Lower than 20% of reused filtering facepiece respirators (FFRs) collected from nurses amid the COVID-19 pandemic had been in ok situation to endure sterilization, after which none retained no less than 94% filtration of aerosol particles, finds a laboratory examine evaluating two sterilization strategies after as much as 15 to 30 days of use.
For the examine, revealed within the American Journal of An infection Management, a College of Sao Paulo-led group in Brazil used a chambered field and an emitted aerosol to guage the bodily traits and post-sterilization filtration of a 5-centimeter (2-inch) sq. fragment from every of 100 reused FFRs (eg, N95s) collected from nurses who cared for COVID-19 sufferers at three hospitals.
Untorn respirators that filtered no less than 94% of aerosolized particles and had an connected nasal clip and elastic bands and no seen grime had been randomly assigned to obtain or not obtain mechanical cleansing with an ultrasonic washer earlier than present process hydrogen peroxide plasma gasoline sterilization.
“Throughout the COVID-19 pandemic, there was a scarcity of Filtering Facepiece Respirators (FFR), resulting in extended use and reuse of FFRs,” the authors famous. “There was additionally an effort to sterilize FFRs aiming to extend the security of healthcare professionals because it was thought that sterilization might scale back self-contamination and defend the surroundings from extra contaminated waste.”
Over 78% of FFRs had been too soiled to sterilize
Of the 1,055 FFRs, over 85% retained secured nostril clips, preserved strap elasticity, and no tears. However over 78% of samples had been soiled (eg, from make-up), leaving solely 19.6% eligible to endure sterilization. Not one of the FFRs—cleaned or uncleaned—reached minimal filtration after sterilization, though 72% of the uncleaned FFRs and 80% of the cleaned units achieved 90.0% to 93.9% filtration.
Sterilization processes utilizing hydrogen peroxide plasma gasoline, each with and with out prior cleansing, utilized to 100 FFRs with preserved performance, didn’t compromise the obvious bodily traits of those respirators, however didn’t keep their filtration ranges to the minimal essential to be thought-about secure.
“Sterilization processes utilizing hydrogen peroxide plasma gasoline, each with and with out prior cleansing, utilized to 100 FFRs with preserved performance, didn’t compromise the obvious bodily traits of those respirators, however didn’t keep their filtration ranges to the minimal essential to be thought-about secure,” the researchers concluded.
