COVID, Personal Protective Equipment
Conditions
Keywords
respirators, n99, COVID-19
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.
Interventions
DEVICEFit 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.
DEVICEFiltration 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
Sponsors
Bangkok Metropolitan Administration Medical College and Vajira Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Intervention model description
N99 respirators will be tested in a group of subjects with qualitative fit test.The filters will be tested for filtration test.The results will be considered as pass or fail
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthcare workers
Exclusion criteria
* Intolerance to exercise * cannot taste bitter sensation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Fit test | Day 1 | pass or fail |
Other
| Measure | Time frame | Description |
|---|---|---|
| Filtration test | Day 1 | percent leakage less than1 percent |
Countries
Thailand
Outcome results
None listed