NCT05148793: ReuseN95

N95 Reuse During COVID-19

Completed Last updated 16 February 2023

What this trial tests

trial in Emergency Medicine in 412 participants. Completed in 31 December 2022.

Timeline

1 April 2021

Primary endpoint
31 December 2022

31 December 2022

Quick facts

Lead sponsor	University of California, San Francisco
Status	Completed
Study type	OBSERVATIONAL
Enrollment	412
Start date	1 April 2021
Primary completion	31 December 2022
Estimated completion	31 December 2022
Sites	1 location across United States

Conditions studied

• Emergency Medicine — all drugs for Emergency Medicine →
• Frontline Providers — all drugs for Frontline Providers →
• Healthcare Worker — all drugs for Healthcare Worker →

Sponsor

University of California, San Francisco

Who can join

18 and older, any sex, with Emergency Medicine or Frontline Providers. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

During critical personal protective equipment (PPE) shortages, such as those associated with the COVID-19 pandemic, Centers for Disease Control (CDC) recommends N95 extended use (wearing the same N95 for multiple patient encounters) and limited reuse (storing an N95 between shifts for use over multiple shifts with or without decontamination) as contingency and crisis capacity strategies, respectively. Many healthcare workers (HCWs) are employing these strategies out of necessity. The sustained performance of these respirators depends on the respirator maintaining its filtration efficiency and its ability to provide an adequate seal (fit) to the user's face. Fit testing is performed when a respirator is issued to the user and on an annual basis thereafter. A user-seal check is then performed whenever a respirator is donned. Previous studies have found repeated donnings/doffings to significantly decrease the respirator's fit. A recent pilot cross-sectional clinical study conducted by the University of California, San Francisco found fit failures of respirators after being worn for 2 shifts. However, more definitive data regarding respirator performance during reuse and extended use are lacking. The investigators plan to address these critical gaps in knowledge by conducting a prospective cohort study to determine the incidence of N95 fit failure when subjected to extended use/reuse in a clinical setting. The investigators plan to enroll 396 ED providers (including physicians, nurses, and staff) when obtaining a new NIOSH approved N95s and performing serial fit tests at the end of each 8-12 hour shift for up to 5 clinical shifts or until N95 failure, whichever is earlier. By carefully measuring fit test failure in a clinical setting, the investigators will be able to provide guidance regarding the safety of N95 extended use and reuse necessitated by the need for PPE conservation. Specifically, the investigators will address the following research questions: 1) how long N95s maintain their fit during extended use, 2) how many times N95s can be donned/doffed and maintain their fit, 3) the ability of a user seal check to indicate fit in the field, 4) what adverse health effects, reports of discomfort, or symptoms are experienced by users during extended use and reuse, 5) what effect does extended use and reuse have on N95 filtration performance, 6) the level of contamination of N95s when subjected to extended use and reuse, 7) the effect of modifications to N95 (covering an N95 with a face shield or surgical N95s, facial coverings) on fit failure.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. N95<sup>®</sup> filtering facepiece respirator contamination with SARS-CoV-2 following reuse and extended use.
   Ford JS, Wang RC, Stephenson B, Degesys NF, et al · · 2025 · PMID 40657985 · DOI 10.1017/ice.2025.92