Electrostatic Energy
FIGURE 36-14
Electrostatic energy - when two insulators are rubbed together.

Static electricity can be induced by rubbing two insulators together Figure 36-14. During this process, one material loses electrons to the other. The insulator losing electrons becomes positively charged. The other insulator gains electrons to become negatively charged.

When these two highly charged surfaces are brought close enough together, electrons leap across the gap causing a spark and canceling out the charge imbalance. This electron transfer can be experienced as an electric shock. It applies to any charged surfaces where the imbalance in charge is great enough to make the electrons leap the gap. The spark can be dangerous. Near fuel vapor at a gas station, it can even cause an explosion.

There have been many fires caused by the operator starting the refueling process, getting back into the vehicle to check on a child or put a credit card away, sliding back out across the seat of the vehicle (without touching the metal of the vehicle), and then grabbing the refueling nozzle, at which time a spark ignites the fumes escaping from the filling tank. Always touch the metal of the vehicle or fuel pump before touching the refueling nozzle. Also, fires have reportedly resulted from customers sliding their plastic gas cans out of the back of a plastic-lined pick-up bed, creating a spark when the nozzle touched the can or when the pour spout touched the gas tank.