Theoretically, any two items or materials brought into contact and then separated can generate static electricity. For the purposes of this handbook, the interactions that are important involve people, electronic and electrical components, handling equipment, and packaging materials, as well as any other item or material that may enter the work area. Once a static charge is generated, a charged surface can influence other items through space at a distance. Induction, as described in the previous section, can result in an ESD event if the conductive/dissipative item is grounded while in the presence of the electric field. This important concept has been shown to cause many difficulties in industry including: explosions, fires, component damage, system disruption, and personnel shock. An isolated or insulated conductor will share a static charge with another isolated or insulated conductor if they touch through a conductive interface. The shared charge will result in an equal voltage on both conductors, but the actual charge on each will depend on the capacitance of the individual objects.
The main sources of static electricity in a manufacturing environment include those listed in Table 1.
Table 1. Typical Static Electricity Sources
It should be understood that any object, item, material, or person could be a source of static electricity in the work environment. Removal of unnecessary insulators, replacing insulative materials with dissipative or conductive materials, and grounding all conductors are the principle methods of controlling static electricity in the workplace, regardless of the activity