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disposable N-95 particulate respirator (Teknol, TB mask)

Indications: - droplet precautions a) SARS, SARS-CoV2 b) tuberculosis c) swine flu Procedure: - sanitization for re-use - exposure to vaporized hydrogen peroxide or ultraviolet (UV) light appears to eliminate the SARS-CoV-2 virus & preserve integrity of the masks' fit for up to 3 uses [4] - dry heat (70 C) also eliminates the virus on masks but is effective for 2 uses rather than 3 [4] - respirators should be stored in a breathable paper bag for at least 5 days between uses & should be limited to a maximum of five wears [12] - steam may sterilize N95 respirators without compromise in fit for up to 3 cycles [5] - irradiating N95 masks with gamma radiation reduces their ability to filter air particles without affecting 'fit test' [6] - steam generated using glass containers, mesh from produce bags, a rubber band, & a microwave useful for 20 decontamination cycles [8] - metal in N-95 mask does not spark microwave - fit & function maintained [8] - ultraviolet germicidal irradiation, moist heat, & microwave-generated steam processing are effective for decontamination & are simple to implement [14] Notes: - N95 means it filters out > 95% of 0.3 uM particles, thus airborne pathogens - commonly available from medical supply outlets & pharmacies - look for package rated 'N95' - while N95 masks appear superior to surgical masks in laboratory settings, data is insufficient to conclude that they offer any better protection against respiratory infection in clinical settings [2] - healthcare workers exposed to patients with Covid-19 have less chance of infection with Covid-19 if wearing an N95/KN95 mask vs a surgical mask (21% vs 35%) [17] - no better than surgical masks in preventing influenza infection in clinical setting [3] - duckbill N95 masks with high rate of fit test failure (71%) among healthcare workers who were using their masks for extended periods [7] - dome-shaped N95 masks with 28% failure rate; failure more likely with increasing duration of use [7] - expired or reused sterilized N95 masks can filter out aerosolized particles [10] - when reused for > 2 days, nearly half of N95 masks fail [11] - N95 makes can be safely re-sterilized with a standard decontamination approach involving vaporized hydrogen peroxide & still maintain their effectiveness for up to 25 cycles of re-use [16] - N95 masks can be reused once without significant loss of filtration efficiency - filtration efficiency dependent on N95 model [18] * Fake 95 masks have flooded the market; here is how to tell the difference [13] * NIOSH* describes 7 signs N95 masks may be fake [15] * NIOSH = CDC's National Institute for Occupational Safety & Health (NIOSH)

General

face mask

References

  1. Prescriber's Letter 10(5):25 2003
  2. Smith JD, MacDougall CC, Johnstone J et al Effectiveness of N95 respirators versus surgical masks in protecting health care workers from acute respiratory infection: a systematic review and meta-analysis. CMAJ. March 7, 2016 PMID: 26952529 http://www.cmaj.ca/content/early/2016/03/02/cmaj.150835.full.pdf+html
  3. Radonovich LJ Jr, Simberkoff MS, Bessesen MT et al. N95 respirators vs medical masks for preventing influenza among health care personnel: A randomized clinical trial. JAMA 2019 Sep 3; 322:824. PMID: 31479137 https://jamanetwork.com/journals/jama/article-abstract/2749214 - Talbot TR, Babcock HM. Respiratory protection of health care personnel to prevent respiratory viral transmission. JAMA 2019 Sep 3; 322:817. PMID: 31479123 https://jamanetwork.com/journals/jama/article-abstract/2749198
  4. Frellick M How to Sanitize N95 Masks for Reuse: NIH Study. Medscape - Apr 17, 2020. https://www.medscape.com/viewarticle/928877
  5. Phend C Steam Clean Checks Out for N95 Sterilization - Small study affirmed efficacy, fit test through three rounds. MedPage Today April 22, 2020 https://www.medpagetoday.com/infectiousdisease/covid19/86086 - Carrillo I, Floyd A, Valverde C et al Immediate Use Steam Sterilization (IUSS) Sterilizes N95 Masks Without Mask Damage. Infection Control & Hospital Epidemiology. April 2020. pg 1-5 PMID: 32299520 https://www.cambridge.org/core/journals/infection-control-and-hospital-epidemiology/article/immediate-use-steam-sterilization-iuss-sterilizes-n95-masks-without-mask-damage/4BDC5CF0BBC9CFB44C0E837B3B37CC83
  6. Cramer A, Tian E, Galanek M et al Assessment of the Qualitative Fit Test and Quantitative Single-Pass Filtration Efficiency of Disposable N95 Masks Following Gamma Irradiation. JAMA Netw Open. 2020;3(5):e209961. PMID: 32453381 Free article https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2766200
  7. Degesys NF, Wang RC, Kwan E et al Correlation Between N95 Extended Use and Reuse and Fit Failure in an Emergency Department. JAMA. Published online June 3, 2020 PMID: 32496504 https://jamanetwork.com/journals/jama/fullarticle/2766940
  8. Zulauf KE, Green AB, Nguyen Ba AN et al Microwave-Generated Steam Decontamination of N95 Respirators Utilizing Universally Accessible Materials. mBio Jun 2020, 11 (3) e00997-20 PMID: 32587063 https://mbio.asm.org/content/11/3/e00997-20
  9. Su-Velez BM, Maxim T, Long JL et al Decontamination Methods for Reuse of Filtering Facepiece Respirators. JAMA Otolaryngol Head Neck Surg. Published online July 2, 2020 PMID: 32614377 https://jamanetwork.com/journals/jamaotolaryngology/fullarticle/2767783
  10. Sickbert-Bennett EE et al. Filtration efficiency of hospital face mask alternatives available for use during the COVID-19 pandemic. JAMA Intern Med 2020 Aug 11; [e-pub]. PMID: 32780113 PMCID: PMC7420816 https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2769443 - Dugdale CM, Walensky RP. Filtration efficiency, effectiveness, and availability of N95 face masks for COVID-19 prevention. JAMA Intern Med 2020 Aug 11; [e-pub] PMID: 32780097 https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2769441
  11. Hein C Don't Use N95 Masks for More Than 2 Days, Research Suggests. Medscape - Nov 02, 2020. https://www.medscape.com/viewarticle/940168
  12. FDA News Release. Nov 25, 2020 Coronavirus (COVID-19) Update: FDA Issues New Policy on Dry Heat for Reuse of Certain Respirators. https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-issues-new-policy-dry-heat-reuse-certain-respirators
  13. Morava M, Andrew S Fake N95 masks have flooded the market. Here's how to tell the difference. CNN News. February 6, 2021 https://www.cnn.com/2021/02/05/us/counterfeit-masks-how-to-spot-trnd/index.html - Example of https://www.cdc.gov/niosh/npptl/usernotices/images/mask-illustrationMisRep.jpg
  14. Schumm MA, Hadaya JE, Mody N et al Filtering Facepiece Respirator (N95 Respirator) Reprocessing. A Systematic Review. JAMA. Published online March 3, 2021 PMID: 33656543 https://jamanetwork.com/journals/jama/fullarticle/2777342
  15. O'Reilly KB 7 signs those new N95s at your physician practice might be fake. JAMA Public Health. March 1, 2021 https://www.ama-assn.org/delivering-care/public-health/7-signs-those-new-n95s-your-physician-practice-might-be-fake
  16. Reuters Staff Researchers Plan for Reusing N95 Respirator Masks. Medscape. Jan 13, 2022 https://www.medscape.com/viewarticle/966508
  17. Hein I Healthcare Workers Who Wear Better Masks Get Less COVID. Observational study affirms better odds of dodging infection by wearing a respirator mask. MedPage Today August 15, 2022 https://www.medpagetoday.com/infectiousdisease/covid19/100227 - Dorr T, Haller S, Muller MF et al Risk of SARS-CoV-2 Acquisition in Health Care Workers According to Cumulative Patient Exposure and Preferred Mask Type. JAMA Netw Open. 2022;5(8):e2226816. PMID: 35969403 https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2795150
  18. Wang RC, Addo N, Degesys NF et al N95 Filtering Facepiece Respirator Reuse, Extended Use, and Filtration Efficiency. JAMA Netw Open. 2024 Oct 1;7(10):e2441663. PMID: 39470642 Free article. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2825446