What is the purpose of bonding all metallic parts in a grounding system?

The purpose of bonding all metallic parts in a grounding system is to establish a common electrical potential for safety. This process ensures that all metallic components, which could potentially become energized during a fault condition, are at the same electrical potential. By doing this, it minimizes the risk of electric shock to individuals who might come into contact with these metallic parts. If there is a fault in the system, bonding allows fault current to easily flow back to the ground, triggering protective devices such as circuit breakers to disconnect the power. This safety mechanism is crucial in preventing hazardous situations, thus enhancing the overall safety of the electrical installation.

The other choices do not accurately reflect the primary safety objective of bonding metallic parts. For instance, enhancing aesthetic value is not a consideration in grounding systems; physical size minimization is related to design efficiency, not safety; and while electrical conductivity is important, the primary function of bonding is related to safety and potential equalization rather than improving conductivity.