Results of Cloth Impregnation

Following are the summarised results from independent laboratories, detailing the anti-microbial activity of fabric impregnated with Endurocide Residual.

Un-Washed Samples

Washed 5 Times at 43°C

Washed 10 Times at 43°C

Note: Shirley Technologies, Ltd. and Evans Vanodine performed the anti-microbial SNV 195 920:1994 tests for the samples listed in the above tables, between June 2004 and June 2005. The results listed herein are summaries based upon their test reports.

Treated fabric is considered to be anti-microbial if no bacterial growth is detected on the fabric sample challenged by the bacteria. If growth is detected, the treated fabric has poor or no anti-microbial activity depending upon the degree of bacteria growth. All samples tested exhibited no bacterial growth.

Another means of determining the effectiveness of treated fabric is to consider the Zone of Inhibition. If the area directly adjacent to the fabric sample does not have any bacteria growth, then this area is referred to as the Zone of Inhibition. This is where the treated cloth repels the bacteria and prevents it from growing near the sample. A Zone of Inhibition around samples indicates superior anti-microbial abilities.

Samples that do not have a Zone of Inhibition still can have good anti-microbial activity, as long as there is no bacteria growth under the sample. The best anti-microbial activity is demonstrated in samples that have both a Zone of Inhibition and no growth under the sample.

Textile Anti-Microbial Impregnation Testing Method

Fabric samples were impregnated with the Endurocide Residual solution at a 4% concentration. These samples were then sent to an independent testing laboratory to gauge their effectiveness against Staphylococcus aureus, Klebsiella pneumonia, Escherichia coli, and MRSA. A 2.5 cm square sample was cut from the treated fabric and was placed on top of each bacteria culture, with sample contact ensured to the culture. After an incubation period of 24 hours at 37°C, the samples were inspected as to their anti-microbial activity.

Several samples were washed 5 or 10 times at a temperature of 43°C before the samples were placed on the bacteria culture and tested. This was to determine the residual strength of the chemical after multiple washings. All tests were conducted in conformance with SNV195 920:1994 and were conducted by Shirley Technologies, Ltd and Evans Vanodine International.

Testing Method of Accelerated Ageing

When fabric is treated with Endurocide Residual, it has been proven to give the cloth anti-microbial properties. Once the material has been treated, it is reasonable to consider the duration of the anti-microbial activity. Currently, there is no European test that directly deals with this. However, there are existing accelerated ageing tests that can be adjusted to examine the weathering and ageing of a biocide treated fabric.

The QUV weathering test is typically used for exterior paint film testing, including their anti-microbial activity, and the method itself is easily adapted.

The QUV weathering test requires the treated fabric to be exposed to a weathering cycle of 120 hours of UV radiation followed by 5 hours of directed water spray.

The treated fabric was tested to a total cycle time of 336 hours. Typically a 336 hour cycle test indicates a life time under direct UK exposure of 12 months. As anti-microbial treated fabric is unlikely to be used outdoors, it is possible that a life time from impregnation of 2−3 years is possible.

Using the precautionary principle, we are able to confirm that the textiles treated with Endurocide Residual (4% solution) will remain anti-microbial for at least 12 months.

Thor Specialities, Limited performed the QUV weathering test. QUV weathering uses a sequence of UV radiation exposure and water spray cycles. A UV−A 340 bulb (with a wavelength range of 315 − 400 nanometers) was selected for these tests. This range is similar to the UV wavelength measured on the surface of the earth.