This test method is based on Test Method F903 for measuring resistance of chemical protective clothing materials to penetration by liquids.  This test method is normally used to evaluate specimens from individual finished items of protective clothing and individual samples of materials that are candidates for items of protective clothing.

 

Finished items of protective clothing include gloves, are shields, aprons, gowns, coveralls, hoods, and boots.

 

The phrase “specimens from finished items” encompasses seamed and other discontinuous regions as well as the usual continuous regions of protective clothing items.

 

Finished items of protective clothing include gloves, arm shields, aprons, gowns, coveralls, hoods, and boots. The phrase “specimens from finished items” encompasses seamed and other discontinuous regions as well as the usual continuous regions of protective clothing items. Medical protective clothing materials are intended to be a barrier to blood, body fluids, and other potentially infectious materials. Many factors can affect the wetting and penetration characteristics of body fluids, such as surface tension, viscosity, and polarity of the fluid, as well as the structure and relative hydrophilicity or hydrophobicity of the materials.

 

Test Method

 

A specimen is subjected to a body fluid simulant (synthetic blood) for a specified time and pressure. Visual observation is made to determine when, or if, penetration occurs.  Any evidence of synthetic blood penetration constitutes failure. Results are reported as pass/fail.

 

2 mL of synthetic blood is sprayed through a small cannula onto the surface of the face mask. At the conclusion of the test, the back side of the medical face mask is observed for synthetic blood penetration. Face masks can be evaluated at three different velocities corresponding to a human blood pressure of 80, 120, and 160 mm Hg. If the mask passes at the highest pressure, there is no need to test the mask at a lower pressure. A single sampling plan providing Acceptable Quality Level (AQL) of 4.0% would require that 32 masks be tested and that 29 of the 32 masks pass the test.

 

The surface tension range for blood and body fluids is approximately 42 – 60 dynes/cm. To simulate the wetting characteristics, the synthetic blood is adjusted to the lower end of this range (40 ± 5 dynes/cm).