Protective clothing against chemicals
Test methods and performance classification of chemical protective clothing materials, seams, joins and assemblages.
This Standard is an umbrella standard calling on other test methods, and providing the classifications for the relevant test methods. Various sections of this standard are required to have been passed prior to undertaking the Type (Whole suit test) tests.
Clause 4.4: Abrasion Resistance
This Clause calls up the BS EN 530 Standard: Abrasion resistance of protective clothing material-Test methods. Method 2 is required, whereby the sample is mounted on a felt backed plate and secured free from wrinkles or folds in the fabric. An abrasive paper 00 (as per Annex A of EN 14325) is used with a downward pressure of 9kPa. The performance is determined in one of two ways, by default the pressure pot method is used. To determine the leak tightness of the test specimen, the tested area is clamped in the pressure pot apparatus and the pressure in the test pot is reduced by 1kPa (10mbar). The difference in the change of pressure between and abraded and non abraded specimen shall not exceed 100Pa (1mbar) in one minute. This is not always applicable e.g. it is not suitable for microporous laminated fabrics, in this instance the assessment is done on a visual basis. The classification is as per EN 14325 Clause 4.4.2 . . . | Class | Number of Cycles |
| 6 | 2000 | |
| 5 | 1500 | |
| 4 | 1000 | |
| 3 | 500 | |
| 2 | 100 | |
| 1 | 10 |
Clause 4.5: Flex cracking resistance
This Clause calls up the BS EN 530 Standard: Abrasion resistance of protective clothing material-Test methods. Method 2 is required, whereby the sample is mounted on a felt backed plate and secured free from wrinkles or folds in the fabric. An abrasive paper 00 (as per Annex A of EN 14325) is used with a downward pressure of 9kPa. This Clause calls up the BS EN ISO 7854 standard: Rubber- or plastics-coated fabrics-determination of resistance to damage by flexing. EN 14126 calls for Method B the Schildknecht method to be used. In this method the specimen is mounted using metal clips onto two cylinders, which through a reciprocating action facilitate the flexing of the specimen. The performance is determined in one of two ways, by default the pressure pot method is used. To determine the leak tightness of the test specimen, the tested area is clamped in the pressure pot apparatus and the pressure in the test pot is reduced by 1kPa (10mbar). The difference in the change of pressure between and abraded and non abraded specimen shall not exceed 100Pa (1mbar) in one minute. This is not always applicable e.g. it is not suitable for microporous laminated fabrics, in this instance the assessment is done on a visual basis. The classification is as per EN 14325 Clause 4.. | Class | Number of Cycles |
| 6 | 100,000 | |
| 5 | 40,000 | |
| 4 | 15,000 | |
| 3 | 5,000 | |
| 2 | 2,500 | |
| 1 | 1000 | |
Clause 4.6: Flex Cracking Resistance at -30°C
This Clause calls up the same standard as Clause 4.5, and the testing method is identical, except for the temperature of the test. The classifications are also different, and these are laid out in EN 14126 Clause 4. This is not always applicable e.g. it is not suitable for microporous laminated fabrics, in this instance the assessment is done on a visual basis. The classification is as per EN 14325 Clause 4.4.2 . . . | Class | Number of Cycles |
| 6 | 4000 | |
| 5 | 2000 | |
| 4 | 1000 | |
| 3 | 500 | |
| 2 | 200 | |
| 1 | 100 |
Clause 4.7 Trapezoidal Tear resistance
This Clause calls up the standard BS EN ISO 9073-4: Textiles-Test methods for nonwovens- Part 4: Determination of Tear resistance. For this test a trapezoid of material is cut from the sample, and mounted into a tensile strength testing machine. The test is repeated five times, with an average being taken from the five readings, the classification for this test is laid out in EN14325 Clause 4.7 | Class | Trapezoidal Tear Resistance |
| 6 | 150N | |
| 5 | 100N | |
| 4 | 60N | |
| 3 | 40N | |
| 2 | 20N | |
| 1 | 10N |
Clause 4.8 Bursting Resistance
This Clause calls up the standard BS EN ISO 13938-1: Textiles-Bursting properties of fabrics- Part 1: Hydraulic method for determination of bursting strength and bursting distension A sample of 50cm2 is clamped over an expansive diaphragm by means of a circular clamping ring. Increasing fluid pressure is applied to the underside of the diaphragm, causing distension of the diaphragm and the fabric. The volume of fluid is increased at a constant rate per unit time until the test specimen bursts. The bursting strength and bursting distension are determined.  |
Clause 4.9 Tensile Strength
This Clause calls up the standard BS EN ISO 13934-1: Textiles-Tensile properties of fabrics- Part 1: Determination of maximum force and elongation at maximum force using the strip method. A fabric specimen of specified dimensions is extended at a constant until it ruptures. The maximum force and the elongation at maximum force and, if required, the force at rupture and the elongation at rupture are recorded. For this test a CRE (Constant Rate of Extension) tensile testing machine is used. Which pulls the sample at a fixed rate until the fabric ruptures. The Classification of this test is laid out in EN 14325 Clause 4.9. | Class | Tensile Strength |
| 6 | 1000N | |
| 5 | 500N | |
| 4 | 250N | |
| 3 | 100N | |
| 2 | 60N | |
| 1 | 30N |
Clause 4.10 Puncture Resistance
This clause calls up the standard EN 863: Protective clothing- Mechanical properties- Test Method: Puncture resistance. The sample is placed between two steel plates, and a metal spike is forced through the sample at a speed of 100(+/-10)mm/min. If the spike has failed to puncture the specimen after movement of 25mm, the test is terminated, as there can be no reliable endpoint determined to test, due to elasticity of the sample. The classification of this test is laid out in EN14126 Clause 4.10. | Class | Puncture Resistance |
| 6 | 250N | |
| 5 | 150N | |
| 4 | 100N | |
| 3 | 50N | |
| 2 | 10N | |
| 1 | 5N | |
Clause 5.5 Seam Strength
A Fabric test specimen having a seam in the middle is gripped in its centre part by jaws of specified dimensions and is extended perpendicularly to the seam at a constant rate until the seam ruptures. The maximum force to seam rupture is recorded. |
This Clause calls up the Standard BS EN ISO 13935-2: Textiles-Seam Tensile properties of fabrics and made-up textile articles- Part 2: Determination of maximum force to seam rupture using the grab method. Resistance to ignition testing
It should be noted that this standard was originally developed to test respiratory protective devices, and that Method 3 the ‘single burner moving specimen test’ is used.
In this method, a sample is passed through a flame on a rotating mechanism travelling at 60 ±5mm/s. The sample is placed 20 ±2mm from the tip of the burner with a flame height of 40 ±4mm and a temperature of 800 ±50°C.
Performance
The performance requirements and classifications for this test are set out in EN 14325 Clause 4.15
“When tested in accordance with EN 13274-4, method 3, modified to comply with the flame exposures in Table 12, the chemical protective clothing shall not form holes or droplets and shall prove top be ‘self-extinguishing’, i.e. it shall not be of a highly flammable nature and when tested shall not continue to burn for more than five seconds after removal from the flame.”
Table 12: Classification of resistance to flame
| Class | Flame Exposure |
| 3 | Specimen stops for five seconds in the flame |
| 2 | Specimen stops for one second in the flame |
| 1 | Specimen passes through the flame without stopping |