DOE-HDBK-1015/2-93
FLAMMABLE AND COMBUSTIBLE LIQUIDS
Hazards of Chemicals and Gases
CH-05
Rev. 0
Page 34
Figure 5 Typical Static-producing Situations, Including Charge Separation in Pipe
The terms bonding and grounding have sometimes been used interchangeably because of a poor
understanding of the terms. As illustrated in Figure 6, bonding eliminates a difference in
potential between objects. Grounding eliminates a difference in potential between an object and
ground. Bonding and grounding are effective only when the bonded objects are conductive.
When two objects are bonded, the charges flow freely between the bodies, and there is no
difference in their charge. Therefore, the likelihood of sparking between them is eliminated.
Although bonding eliminates a difference in potential between the objects that are bonded, it
does not eliminate a difference in potential between these objects and the earth unless one of the
objects possesses an adequate conductive path to earth. Therefore, bonding will not eliminate
the static charge, but will equalize the potential between the objects bonded so that a spark will
not occur between them.
An adequate ground will discharge a charged conductive body continuously and is recommended
as a safety measure whenever any doubt exists concerning a situation.