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Sponsor: Sinh Nguyen
Vietnam Project LLC
One Boston Place Boston, MA 02108

Latex Particle Challenge Final Report 

Test Article: Lot# QKR03012021 
Study Number: 1404800-S01
Study Received Date: 02 Apr 2021 
Testing Facility: Nelson Laboratories, LLC 
6280 S. Redwood Rd
Salt Lake City, UT 84123 U.S.A.
Test Procedure(s): Standard Test Protocol (STP) Number: STP0005 Rev 08 
Deviation(s): None 

Summary: This procedure was performed to evaluate the non-viable particle filtration efficiency (PFE) of the test article. Monodispersed polystyrene latex spheres (PSL) were nebulized (atomized), dried, and passed through the test article. The particles that passed through the test article were enumerated using a laser particle counter.
A one-minute count was performed, with the test article in the system. A one-minute control count was performed, without a test article in the system, before and after each test article. Control counts were performed to determine the average number of particles delivered to the test article. The filtration efficiency was calculated using the number of particles penetrating the test article compared to the average of the control values. During testing and controls, the airflow rate is maintained at 1 cubic foot per minute (CFM) +/- 5%.
The procedure employed the basic particle filtration method described in ASTM F2299, with some exceptions; notably the procedure incorporated a non-neutralized challenge. In real use, particles carry a charge, thus this challenge represents a more natural state. The non-neutralized aerosol is also specified in the FDA guidance document on surgical face masks. All test method acceptance criteria were met. Testing was performed in compliance with US FDA good manufacturing practice (GMP) regulations 21 CFR Parts 210, 211 and 820.

Test Side:   Inside
Area Tested:   91.5 cm2
Particle Size:   0.1 um
Laboratory Conditions:   22.5°C, 21% relative humidity (RH) at 1516; 21.6°C, 22% RH at 1619
Average Filtration Efficiency:   99.53
Standard Deviation:   0.135


FDA Medical Device Registration