National Electrical Code Top Ten Tips: Article 514 -- Motor Fuel Dispensing Facilities
- Article 514 covers any structure used for storing or dispensing
fuel from fixed equipment. It also applies to fuel dispensing
facilities for fleets [514.1]. With the 2020 revision, Information Note 2 was added. It says some text (identified by virtue of being in brackets) was extracted from NFPA-218, Code for Motor Fuel Dispensing Facilities and Repair Garages. It would be good to use both of thes code books at the same time, even if you are doing electrical work only.
- Article 514 distinguishes between locations handling Class I
liquid fuels and those handling three other fuels: compressed
natural gas, liquefied natural gas, and liquefied petroleum gas
[514.3]. This has been heavily revised with the 2020 revision.
- Table 514.3(B)(1) defines Class I locations for the purposes of
Article 514. It's a big table.
- Table 514.3(B)(2) defines electrical equipment classified areas
for fuel dispensing. It's a small table.
- Equipment covered by Table 514.3(B)(1) must be wired per Article
501 [514.4]. That's because you're dealing with flammable vapors.
- Equipment located above equipment covered by Table 514.3(B)(1)
must comply with 511.7 [514.7]. Article 511 provides the requiremens for commercial garages used for repair and storage..
- Install underground wiring in threaded metal conduit, not EMT or
PVC [514.8]. Some exceptions apply.
- Provide a listed seal in each conduit (here, we can refer to the
raceways as conduit because in this case they are) entering or
leaving a dispenser. The sealing fitting must be the first fitting
after the conduit emerges from the earth or concrete [514.9(A)].
- In addition to the dispenser seals, provide seals at the
horizontal and vertical boundaries of the defined Class I locations
[514.9(B)].
- Bond all metal raceways and metallic objects [514.16],
taking care not to confuse grounding with bonding [Article 100].
Grounding and bonding are not interchangeable procedures, and they
do not accomplish the same things. If in doubt, bond instead of
ground.
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