The New Silicone N99 Half-Piece Respirator

NCT ID: NCT04454606

Last Updated: 2020-07-01

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 43 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2020-05-01
• Study Completion Date: 2020-05-31

Brief Summary

Filter facepiece respirator (FFR) is a critical equipment to prevent the transmission of respiratory tract infection disease especially the dreadful corona virus 2(SARs-CoV-2).The N95 mask is the prototype of high efficiency protective device and can effectively protect airborne pathogens of less than 0.3 μm by more than 95%. It is tightly fit and had high filtration capacity. The widespread pandemic of COVID-19 leads to greater requirement of FFR. A rising in demand would greatly exceed current productive capabilities and stockpiles and would almost certainly result in a robust shortage.

In order to solve these problems, our team had invented a new type of half-piece respirator made from silicone and assembled with hepa or elastostatic filter . A variety of methods have been used to evaluate this new device, including qualitative fit test with Bitrex® test kit and filtration test.

Detailed Description

As required by Occupational Safety and Health Administration OSHA)[7], the halfpiece respirators need to pass the fittestto identify those individuals who do not achieve the good fit necessary for adequate protection. The performance of this respirator was also determined by measuring percent leakage under constant airflow[8]. The purposes of this study was to evaluate the fitting characteristicof our newly invented silicone N99 respirator and the performance against 30 µm particles using NaCL aerosols. The study was conducted to achieve two specific research objectives

1. To investigate the fit characteristic of the novel silicone mask and whether the strap adjustment can help reduce the face-seal leakage

2. To determine the level of performance by measure the inward leakage of the generated aerosolswith the new filter and used filter for up to 24 hours.

Conditions

COVID; Personal Protective Equipment

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: PREVENTION
• Blinding Strategy: NONE

Study Groups

Fit test

All the subjects will be tested for fit test

Group Type: EXPERIMENTAL

Fit test

Intervention Type: DEVICE

Bitrex Fit Test The Bitrex test uses a person's ability to test a bitter solution to determine whether a respirator fits properly[11]. Each subject was given a taste-threshold screening test prior to each fit test to ensure that he or she could taste. This process was done without subject wearing a respirator. After passing the sensitivity test, the subject will process to 7 steps of fit test as following

• Breathe normally
• Breathe deeply
• Head side to side
• Head up and down
• Bent over wrist, jogging
• Talking
• Breath normally Each step took 60 seconds and the Bitrex solution was refilled into the hood every 30 seconds with half dosage of the amount of the previously test. We asked the participant if he / she could taste the solution during each steps of the test . The test was considered a failure, otherwise, a pass.

Filtration Test

Intervention Type: DEVICE

Respirator Performance

The real time respirator performance test method was developed using MT-05U machine (SIBATA model, Saitama, Japan), which measure particle concentrations of diameter 0.03 - 0.06 µm using and particle generator laser beam scattering particle counter that measure particles outside and inside the mask. The ratio between these two values reflected % leak as following:

• leak=((Paticle inside the filter))/((Paticle inside the filter)) x 100 And calculate % filter performance = 100 - % leak We tested at the airflow rate of 40L/min which is 3-4 times higher than normal physiology, assuming that there should be no leakage through the filter. We tested 2 types of filter is CareStar and SafeStar that was incorporated with the silicone mask. CareStar is limited for 24 hour usage and SafeStar is for 72 hour duration.

Study protocol

Interventions

Fit test

Bitrex Fit Test The Bitrex test uses a person's ability to test a bitter solution to determine whether a respirator fits properly[11]. Each subject was given a taste-threshold screening test prior to each fit test to ensure that he or she could taste. This process was done without subject wearing a respirator. After passing the sensitivity test, the subject will process to 7 steps of fit test as following

• Breathe normally
• Breathe deeply
• Head side to side
• Head up and down
• Bent over wrist, jogging
• Talking
• Breath normally Each step took 60 seconds and the Bitrex solution was refilled into the hood every 30 seconds with half dosage of the amount of the previously test. We asked the participant if he / she could taste the solution during each steps of the test . The test was considered a failure, otherwise, a pass.

Intervention Type: DEVICE

Filtration Test

Respirator Performance

The real time respirator performance test method was developed using MT-05U machine (SIBATA model, Saitama, Japan), which measure particle concentrations of diameter 0.03 - 0.06 µm using and particle generator laser beam scattering particle counter that measure particles outside and inside the mask. The ratio between these two values reflected % leak as following:

• leak=((Paticle inside the filter))/((Paticle inside the filter)) x 100 And calculate % filter performance = 100 - % leak We tested at the airflow rate of 40L/min which is 3-4 times higher than normal physiology, assuming that there should be no leakage through the filter. We tested 2 types of filter is CareStar and SafeStar that was incorporated with the silicone mask. CareStar is limited for 24 hour usage and SafeStar is for 72 hour duration.

Study protocol

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Healthcare workers

Exclusion Criteria

• Intolerance to exercise
• cannot taste bitter sensation

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Bangkok Metropolitan Administration Medical College and Vajira Hospital

OTHER_GOV

Sponsor Role: lead

Responsible Party

Thananda Trakarnvanich

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Thananda Trakarnvanich, M.D.

Role: STUDY_DIRECTOR

Bangkok Metropolitan Administration and Vajira Hospital

Locations

Bangkok Metroplitan Administration and Vajira Hospital

Bangkok, , Thailand

Countries

Thailand

References

Gralton J, Tovey E, McLaws ML, Rawlinson WD. The role of particle size in aerosolised pathogen transmission: a review. J Infect. 2011 Jan;62(1):1-13. doi: 10.1016/j.jinf.2010.11.010. Epub 2010 Nov 19.

Reference Type: BACKGROUND

PMID: 21094184 (View on PubMed)

5.Occupational Safety and health Administration(OSHA): 29 CFR parts 1910 and 1926 Respiratory Protection: Final Rule. Federal Register 63(5): 1278-1279. Washington, D.C: U.S. Government Printing Office, Office of the Federal Register, January 8,1998.

Reference Type: BACKGROUND

Coffey C, Zhuang Z, Campbell D. Evaluation of the BitrixTM qualitative fit test method using N95 filtering-facepiece respirators. J Int Soc Respir Prot 1998: 16 : 48-55.

Reference Type: BACKGROUND

Leung NHL, Chu DKW, Shiu EYC, Chan KH, McDevitt JJ, Hau BJP, Yen HL, Li Y, Ip DKM, Peiris JSM, Seto WH, Leung GM, Milton DK, Cowling BJ. Author Correction: Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med. 2020 Jun;26(6):981. doi: 10.1038/s41591-020-0946-9.

Reference Type: RESULT

PMID: 32461699 (View on PubMed)

Other Identifiers

053/2563

Identifier Type: -

Identifier Source: org_study_id