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Specificity of UV-C LED disinfection efficacy for three N95 respirators.

ABSTRACT: The recent surge in the use of UV technology for personal protective equipment (PPE) has created a unique learning opportunity for the UV industry to deepen surface disinfection knowledge, especially on surfaces with complex geometries, such as the N95 filter facepiece respirators (FFR). The work outlined in this study addresses the interconnectedness of independent variables (e.g., UV Fluence, respirator material) that require consideration when assessing UV light efficacy for disinfecting respirators. Through electron microscopy and Fourier-transform infrared (FTIR) spectroscopy, we characterized respirator filter layers and revealed that polymer type affects disinfection efficacy. Specifically, FFR layers made from polypropylene (PP) (hydrophobic in nature) resulted in higher disinfection efficiency than layers composed of polyethylene terephthalate (PET-P) (hygroscopic in nature). An analysis of elastic band materials on the respirators indicated that silicone rubber-based bands achieved higher disinfection efficiency than PET-P bands and have a woven, fabric-like texture. While there is a strong desire to repurpose respirators, through this work we demonstrated that the design of an appropriate UV system is essential and that only respirators meeting specific design criteria may be reasonable for repurposing via UV disinfection.

SUBMITTER: Ontiveros CC

PROVIDER: S-EPMC8319424 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Can N95 Respirators Be Reused after Disinfection? How Many Times?

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| S-EPMC7737533 | biostudies-literature

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Efficacy and safety of disinfectants for decontamination of N95 and SN95 filtering facepiece respirators: a systematic review.

Project description:BackgroundDecontaminating and reusing filtering facepiece respirators (FFRs) for healthcare workers is a potential solution to address inadequate FFR supply during a global pandemic.AimThe objective of this review was to synthesize existing data on the effectiveness and safety of using chemical disinfectants to decontaminate N95 FFRs.MethodsA systematic review was conducted on disinfectants to decontaminate N95 FFRs using Embase, Medline, Global Health, Google Scholar, WHO feed, and MedRxiv. Two reviewers independently determined study eligibility and extracted predefined data fields. Original research reporting on N95 FFR function, decontamination, safety, or FFR fit following decontamination with a disinfectant was included.Findings and conclusionA single cycle of vaporized hydrogen peroxide (H2O2) successfully removes viral pathogens without affecting airflow resistance or fit, and maintains an initial filter penetration of <5%, with little change in FFR appearance. Residual hydrogen peroxide levels following decontamination were within safe limits. More than one decontamination cycle of vaporized H2O2 may be possible but further information is required on how multiple cycles would affect FFR fit in a real-world setting before the upper limit can be established. Although immersion in liquid H2O2 does not appear to adversely affect FFR function, there is no available data on its ability to remove infectious pathogens from FFRs or its impact on FFR fit. Sodium hypochlorite, ethanol, isopropyl alcohol, and ethylene oxide are not recommended due to safety concerns or negative effects on FFR function.

| S-EPMC7423630 | biostudies-literature

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