Static Electricity 2000 Edition

5.8 Assessment of Bonding and Grounding.
5.8.1
As defined in Chapter 3, bonding is a process whereby
two or more conductive objects are connected together by
means of a conductor, so that they are at the same electrical
potential; that is, the voltage difference between the objects is
zero (0). The objects might or might not be at the same poten-
Conductive materials
Semiconductive materials
Nonconductive materials
(a) Volume resistivity
Conductive materials
Semiconductive materials
Nonconductive materials
1
10
2
10
4
10
6
10
8
10
10
10
12
10
14
ohm-m
10
6
10
8
10
10
10
12
10
14
10
16
10
18
ohm-m
10
4
(b) Surface resistivity

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CONTROL OF STATIC ELECTRICITY HAZARDS
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2000 Edition
tial as the earth. In fact, a considerable potential difference
between the objects and the earth could exist.
Grounding is the process of connecting the conductive
objects to the earth, so that they are all at zero (0) electrical
potential.
In both cases, the intent is to eliminate the occurrence of a
static electric spark.
5.8.2
Identification of conductive equipment and objects
within a process is critical for successful bonding and ground-
ing. Periodic inspection and testing of bonding and ground-
ing systems is equally important. Proper inspection and testing
will ensure that the chances for a static electric charge to accu-
mulate are minimized.
5.8.3
The resistance to ground of the bonding or grounding
path is important, not only to ensure relaxation of the static
electric charge, but also to maintain worker safety and satisfy
other purposes, such as those for lightning protection and
electrical system shock protection. Practices that constitute
proper resistance to ground will vary from application to
application. Chapters 6 through 9 provide examples of accept-
able grounding practices.