Material requirements

A material intended to dissipate electrostatic charges must meet at least one of the following requirements:

• t50% < 4 s or S > 0.2, verified according to test method 2 (induction charging) specified in EN 1149-3.

or else

• a surface resistance less than or equal to 2.5 x 109 Ω, verified according to EN 1149-1, on at least one surface.

For a material containing grids or stripes of conductive threads the spacing between conductive threads in one direction must not exceed 10 mm.

Material requirements (standard EN 1149:1995)

For homogeneous materials the surface resistivity after testing must be less than 5 x 1010 Ω

For inhomogeneous materials which are coated or laminated, at least one surface must comply with the requirement for homogeneous materials.

Inhomogeneous materials containing conducting threads must have:

1. at least one surface with no resistances measured to be greater than 10⁹ Ω;
2. a grid pattern of conductive fibres;
3. a maximum spacing of 10 mm between conductive fibres.