¹ EN ISO 6530:2005 Protective clothing. Protection against liquid chemicals. Test method for resistance of materials to penetration by liquids

ANNEXE 4: FABRIC TESTING

LIQUID PENETRATION AND REPELLENCY TEST The liquid penetration and repellency test is performed according to EN ISO 65301 (superseding EN 368) and is often referred to as the Gutter Test .

SCHEMATIC OF THE TEST APPARATUS

In this test, the protective material to be tested is placed in an inclined gutter (45°) which is lined with an absorptive detector fabric. 10 ml of liquid is applied in 10 seconds onto the top of the test material via a syringe needle.

Detector beaker to collect and measure repelled liquid

PENETRATION INDEX

Any liquid which penetrates the fabric via the fabric pores within 1 minute is absorbed by the detector fabric and expressed as percentage of the original quantity and is a measure of the penetration of the fabric.

CHEMICAL MIXTURES Permeation characteristics of a mixture of chemicals can often deviate considerably from the behaviour for the individual chemicals. If protection against

a mixture of hazardous chemicals is required, we recommend you contact the manufacturer for expert advice.

REPELLENCY INDEX

The amount of liquid collected in the beaker after 1 minute is expressed as percentage of the original quantity and is a measure of the repellency of the fabric. Note that EN ISO 6530 only requires four chemicals to be tested. Caution should be applied when interpreting penetration results since the test simulates exposure to small amounts of chemicals (10 ml) and short time (1 minute) only. Furthermore, for volatile chemicals it should be considered that some of the test substances would have evaporated during the test which can falsify the penetration data obtained. This is why EN ISO 6530 states that volatile substances (and their results) have to be identifi ed as such. A protective clothing material with excellent results in the penetration test may give only poor protection when exposed to the same chemical in larger quantities and/or for extended time.

To determine whether a protective clothing material with a low penetration index is really a protection against a specifi c liquid chemical, the chemical permeation data needs to be consulted. T

NO CHEMICAL PERMEATION DATA FOR YOUR CHEMICAL? DuPont can facilitate the independent permeation testing of your specifi c chemical or chemical mixtures with the DuPont berrier fabrics.

Figure 5. Gutter Test.

Annexe 4

Test material

Splash nozzle

Supportive gutter

Absorptive detector material to measure penetrated liquid

Source: DuPont.

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