EN 1149 - Electrostatic properties

UNE EN 1149-1 Electrostatic properties. Surface resistivity (test methods and requirements)

Fabrics which meet this EN ISO standard:

This test method is not applicable to fabrics with conductive fiber core.
Homogeneous material: material in which the electrical properties of its components (wires layers) do not differ substantially from each other, or material containing an intimate mixture of conductive fibers

Test method: the sample is placed on an insulating base plate, then place the group of electrodes on the sample, apply a continuous stream and measure the resistance of  the sample

Requirements:  the surface resistivity must be less than 5 · 10¹⁰ Ω

The inhomogeneous material must have a conductive yarn net and the maximum distance between this conductive threads must be of 10 mm.

UNE EN 1149-2 Electrostatic properties. Test methods for measurement of  the electrical resistance through a material (vertical resistance)

This standard does not apply to specify the protection against electrical stresses

The electrodes are placed on opposite surfaces of the test material. Apply a DC voltage to the electrodes and determining the electrical resistance of the tested material

UNE EN 1149-3 Electrostatic properties. Test methods for measurement of charge decay

The test methods are applicable to all materials, including homogeneous materials and heterogeneous forms of fiber materials with conducting surface and / or conductive fibers with conductive fiber core.

Charging by induction: the burden of the test sample is performed by inductive effect. Immediately below the test sample, which remains horizontal and no contact with it, an electrode is placed in the field. The field electrode is subjected to high voltage abruptly. If the sample is conductive or contain conductive elements is induced on it a charge opposite to the field electrode. Electrode field incident on the conductive elements does not cross the sample and the resulting field is reduced in a manner that is characteristic of the material tested. This effect is measured and recorded by behind of the sample with a probe of appropriate action.
The resulting field measured by the probe-mediated decreases the load induced on the sample size increases. This reduction of field is used to determine the time of semi-dissipation and protection coefficient.

EN 1149-5 Electrostatic properties. Material performance and design requirements

This standard specifies requirements for materials and design of protective clothing with electrostatic dissipation, used as part of a complete set grounded to avoid incendiary discharges. These requirements may not be sufficient in flammable atmosphere rich in oxygen. This European Standard is not applicable for protection against voltage.

Equipment requirements:
An electrostatic dissipating material must meet at least one of the following requirements:
- t50 < 4s or S > 0.2 tested according to EN 1140-3 Method 2 (induction charging)

- surface resistance equal to or less than 2.5 x 109 Ω in at least one of the surfaces tested according to the norm EN 1149-1