An interventional study of SEEUS95 Transparent mask and CrystalGuard Mask in Respiratory Disease, Infection, Coronavirus and Respiratory Tract Infections, sponsored by Brigham and Women's Hospital. Withdrawn at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-07-28.
Sponsored by Brigham and Women's Hospital · Not applicable, Interventional, and Device feasibility
Face masks have become a critically important public health intervention after the COVID-19 pandemic. Multiple types of masks ranging from full face filtering to cloth masks have been developed and commercialized to facilitate protection against respiratory pathogens. Most of these systems are made with opaque fabrics and may prevent individuals from expressing emotions or for those who are deaf and hard of hearing, communicating. To date, few transparent face masks which also confer respiratory pathogen protection have been developed. This study will test the feasability and acceptability of two new masks, the SEEUS-95 mask and CrystalGuard mask which are both transparent versions of N-95 filtering face masks.
This is a randomized crossover trial to evaluate the feasibility, acceptability and choice between the use of the SEEUS-95, CrystalGuard transparent face masks or a standard N95 mask. Otherwise healthy individuals will be prescreened and then scheduled for a single study visit. Participants will be randomized to wear each of the three masks (SEEUS-95, CrystalGuard, N95). They will be taught how to wear the mask, and we will assist participants with correctly wearing the mask for a good fit. Next, participants will undergo standard FIT testing where a clear hood will be placed over the participant's head, and a bitter solution (Bitrex) is sprayed into the hood. A positive test is indicated if the participant is able to taste Bitrex demonstrating that there is a detected leak within the mask. After a few minute washout period, participants will undergo FIT testing of subsequent masks. We will ask participants to rate the comfort of wearing the masks, willingness to wear masks in public and suggestions for improvement in mask design. Finally, we will conduct a discrete choice test to ask participants which mask they would prefer to wear in public.
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Exclusion Criteria:
Transparent mask developed by SEEUS95
Device: SEEUS95 Transparent mask
Transparent mask developed at BWH
Device: CrystalGuard Mask
Standard N95 face mask
Device: N95 face mask
SEEUS95 developed transparent filtering mask
Also known as: SEEUS95
CrystalGuard transparent mask
Also known as: CrystalGuard
Standard N95 style face mask
Also known as: N95
Acceptability
User acceptability and comfort wearing the assigned mask graded on a likert scale
Time frame: immediately after mask wearing
Mask preference
Discrete choice of SEEUS-95, CrystalGuard versus standard N-95 mask selected by study participants
Time frame: immediately after completion of all three arms
Plan to share: No
No publications or documents are linked to this record.
This study is withdrawn, as verified in Jul 2025. You cannot join it, but the record below documents what was studied.
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Brigham and Women's Hospital