In the Synthetic Blood Penetration – Liquid Barrier test procedure, test specimens are prepared by randomly cutting the test material into approximately 75 mm x 75 mm swatches. These are conditioned at 21 ± 5ºC and 30 – 80% relative humidity for at least 24 hours.
Individual test specimens are then loaded into the penetration test cell with the outside of the material facing the reservoir. The test cell reservoir is filled with approximately 60 mL of synthetic blood and allowed to sit for five minutes at atmospheric pressure. After the initial five minutes, an external air source is connected to the test cell and a pressure of 2 psig (pounds per square inch gauge) is applied to the sample for one minute. After one minute of applied pressure, the pressure is released and the specimen then sits for an additional 54 minutes at atmospheric pressure which completes the test phase.
The surface of the specimen is observed for penetration during each stage of testing. The testing results are scored as pass or fail, depending on whether synthetic blood penetration occurred.
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 (42 ± 2 dynes/cm).
If you have additional questions about Synthetic Blood Penetration testing, or would like to consult with the experts at Nelson Labs, just send us a request or call us at (801) 290-7500.