fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
Section/Paragraph: 250.104(B)(5)
New Text
250.104 Bonding of Piping Systems and Exposed Structural Metal.
....
(B) Other Metal Piping.
If installed in, or attached to, a building or structure, a metal piping system(s), including gas piping, that is likely to become energized shall be bonded to any of the following:
(1) Equipment grounding conductor for the circuit that is likely to energize the piping system
(2) Service equipment enclosure
(3) Grounded conductor at the service
(4) Grounding electrode conductor, if of sufficient size
(5) One or more grounding electrodes used, if the grounding electrode conductor is of sufficient size
The bonding conductor(s) or jumper(s) shall be sized in accordance with 250.122, using the rating of the circuit that is likely to energize the piping system(s). The points of attachment of the bonding jumper(s) shall be accessible.
Substantiation
250.104(B)(4) requires the GEC that the pipe is bonded to be at least the size required by the last paragraph of 240.104(B) (The bonding conductor(s) ....). The same size requirement should apply to 240.104(5) since the bonding serves two purposes:
1) connecting the pipe to "earth"
2) connecting the pipe to the grounded conductor to provide a path capable of tripping the OCPD.
If it were only to serve the first purpose, then the GEC would suffice and the last clause of 240.104(B)(4) would not be necessary.
Inserted Deleted
New Text
250.104 Bonding of Piping Systems and Exposed Structural Metal.
....
(B) Other Metal Piping.
If installed in, or attached to, a building or structure, a metal piping system(s), including gas piping, that is likely to become energized shall be bonded to any of the following:
(1) Equipment grounding conductor for the circuit that is likely to energize the piping system
(2) Service equipment enclosure
(3) Grounded conductor at the service
(4) Grounding electrode conductor, if of sufficient size
(5) One or more grounding electrodes used, if the grounding electrode conductor is of sufficient size
The bonding conductor(s) or jumper(s) shall be sized in accordance with 250.122, using the rating of the circuit that is likely to energize the piping system(s). The points of attachment of the bonding jumper(s) shall be accessible.
Substantiation
250.104(B)(4) requires the GEC that the pipe is bonded to be at least the size required by the last paragraph of 240.104(B) (The bonding conductor(s) ....). The same size requirement should apply to 240.104(5) since the bonding serves two purposes:
1) connecting the pipe to "earth"
2) connecting the pipe to the grounded conductor to provide a path capable of tripping the OCPD.
If it were only to serve the first purpose, then the GEC would suffice and the last clause of 240.104(B)(4) would not be necessary.
Inserted Deleted