EPA equipment, surfaces and furniture

Equipment used in an EPA should conform to the requirements over the full range of operational atmospheric humidity conditions.

It is not necessary to use all the items specified – however if any item is used, it must conform to the specification given.

Working surfaces and storage racks, trolleys, carts

Any surfaces on which ESDS are placed must be connected to EPA ground, and have a point-to-point resistance between 10⁴ W and 10¹⁰W, and resistance-to-ground between 7.5x10⁵W and 10⁹ W. It is permissible to "hard ground" (<10⁴W ) surfaces when approved by the ESD Co-ordinator.

Surface to ground resistance values may be achieved by including discrete resistors in the ground path, or by the resistance of the material which is directly grounded.

Floors & footwear

Use of a compliant floor is strongly recommended in 61340-5-x, particularly for new installations. However an EPA does not have to include a compliant floor. If the EPA does not include a floor, ESD protective packaging must be used when moving sensitive devices between EPA workstations - as in any situation where ESDS are transported outside an EPA. 

EPA floor surfaces must have a surface-to-EPA ground resistance of <10⁹W. (N.B. A minimum resistance-to-ground may be required due to safety considerations). The personnel-to-ground resistance of a footwear-flooring combination (for grounding personnel) is recommended to be between 7.5x10⁵W and 3.5x10⁷W .

The resistance from the wearer’s body to EPA ground (metal plate) should be between 5x10⁴W and 10⁸W (and at least 10⁵W for each shoe)

Seating

If seats are used, the resistance to groundable point, from any area of the seat which may have contact with personnel, must be less than 10¹⁰W. At least two wheels or feet must provide a path to ground.

Garments

Compliant garments must be clearly marked and must completely cover all clothing in the arms & torso region. There must be electrical continuity between all parts. The point-point resistance over the outer surface must be less than 10¹²W. Decay of charge on the outer surface to less than 10% of initial value within 2 sec. is required.

Gloves and finger cots

Decay of charge to less than 10% of initial value within 2 sec. is required.

Ionisers

Ionisers must bring the potential due to charge (of either polarity) on items to be brought from 1000V to less than 100V in less than 20 seconds.

Tools, machinery, dispensers and test equipment

Tools should not have insulating handles. Soldering irons must have grounded tips. Any non-insulating part of a tool must be grounded (resistance-to-ground less than 10¹²W). Decay of charge to less than 10% of initial value within 2 sec. is required.

Trolleys and carts

These must have a groundable point. Surfaces must have a point-to-point resistance between 10⁴W and 10¹⁰W, and resistance-to-ground between 7.5x10⁵W and 10⁹W. It is permissible to "hard ground" (<10⁴W ) surfaces when approved by the ESD Co-ordinator. At least two wheels must provide a path to ground.