Filtering performances of 20 protective fabrics against solid aerosols

Abstract

Workers can be exposed to solid airborne particles in some occupational environments, and they might be required to wear chemical protective clothing to prevent skin exposure. Dedicated standards exist to certify the protective value of such clothing, but they are not informative enough to identify the main pathways of entry for solid particles nor to compare performances between different chemical protective clothing. In this work, 20 nonwoven fabrics used to make chemical protective clothing for solid particle protection were selected to be examined for both filtration and comfort performances. Nine were microporous fabrics (MP), 10 were multilayered nonwoven fibrous media (SMS) and one was a flash spun material (FS). To assess their filtration performances, fabrics were challenged in a benchtop wind tunnel with a 20-3,000 nm diameter sodium chloride aerosol at three low fabric face velocities (0.05, 0.15, 0.3 cm/sec). Airflow resistance and water vapor transmission rate were also measured to provide indications of comfort for the wearer. The penetration results led to the classification of the 20 fabrics into distinct groups of filtration efficiency. The data were analysed based on the porous media characteristics (thickness, fiber diameter, porosity, etc.). MPs were the most efficient fabrics, and SMSs showed a wide range of performances, mostly due to variations in the thickness of the filtering layer as well as to the fabric treatment. Measurements of airflow resistance and water vapor transmission rates revealed major differences between MPs and FSs and SMSs. This highlights the potential of some SMS fabrics to meet a compromise between protection and comfort.

Potential Penetration of Engineered Nanoparticles under Practical Use of Protective Clothing Fabrics

“…Fabric characteristics such as fiber and fabric thickness, porosity, fiber diameter, hydrophobicity, and packing density play a major role in determining the filter efficiency and penetration percentages of common lab coats. ,,− The four fabric types chosen for this study represent commonly used lab coats for protection against ENP exposure with varying physical characteristics. ENP characteristics also play an important role in the penetration and filtration efficiency of the fabrics.…”

Dynamic swatch testing of liquid aerosols in a laboratory-sized recirculating wind tunnel

“…Dedicated standards exist to certify the protective value of such clothing, but due to the differences in assessment and specific requirements for target products, the relevant test methods for such protective clothing performance vary greatly 4 , 5 . In particular, the test standard for civilian chemical protective clothing providing protection against airborne solid chemicals (Type 5) offers a relatively realistic test protocol.…”

Comparison of standards for chemical protective clothing on performance requirements and measurements

“…Many studies investigated the aramid fabrics [1], silica aerogel-integrated nonwoven protective fabrics [2], filter material [3], functional coating [4] or cooling system [5] for chemical protective clothing. Also, some studies were conducted to investigate the different types of chemical protective clothing from different aspects.…”