Research: Using Clinically Relevant Test Soils to Evaluate Personal Protective Materials

Effective personal protective equipment (PPE) is critically important to preventing the spread of infectious diseases. Appropriate test systems and test soils are needed to adequately evaluate PPE. ASTM test method F903, which specifies the test method setup also used in ASTM F1670/F1670M-17a and ASTM F1671/F1671M-13, has been used for decades to test liquid penetration resistance of fabrics. All three standards require at least 60 mL of challenge liquid, such as synthetic blood solution (F1670) or bacteriophage in nutrient broth (F1671). The three ASTM test methods also are labor intensive and prone to exhibiting problems with leakage around the gaskets. Previous work comparing the F903 test apparatus with a modified dot-blot apparatus to evaluate the visual penetration of a blood test soil in series of commercially available gowns and drapes demonstrated that the methods are comparable and revealed that penetration through PPE material may depend on the test solution. The study described here evaluated a series of clinically relevant test soils (blood, vomit, urine, and feces) in penetration of PPE garments using the modified dot-blot apparatus. The results indicated that a vomit test soil penetrates PPE material more often than blood, urine, or fecal test soils and that the blood test soil has the least number of PPE failures. Incorporating clinically relevant, chemically defined test soils to evaluate PPE material should be considered to protect healthcare workers and reduce the spread of infectious material.