You've hit on a common issue in construction: ambiguity in the contract documents! Here's a breakdown of how the NEC and general construction practices might interpret your situation, along with some advice

NEC Definition & Interpretation
Wiring (General Definition)

The NEC doesn't provide a single, all-encompassing definition of "wiring." It refers to "wiring methods" extensively, encompassing conductors, raceways, and supporting hardware that constitute the electrical system.

Implicit Inclusion

While not explicitly stated, the intent of "wiring" in the context of a hazardous location is generally understood to include all electrical components within that classified area that are part of the electrical circuit. This can include receptacles and switches, if they are within the boundaries of the classified location and connected to the electrical system within that area.

Article 100 Definitions (NEC)

Article 100 provides fundamental definitions. Look for definitions like "Equipment" (which could arguably include receptacles and switches as 'utilization equipment'), "Raceway," "Conductor," etc. These definitions help frame the broader understanding of what constitutes the electrical system.

Hazardous (Classified) Locations

NEC Article 500 is crucial. It defines Class I, Division 1 locations and mandates the use of intrinsically safe or explosionproof equipment. Article 514, Gasoline Dispensing and Service Stations, specifies the boundaries of classified areas around fuel dispensers.

Analysis of Your Situation1. Ambiguity is Key

The contract documents have ambiguity. The note states ALL WIRING INSTALLED AT FUELING STATION SHALL BE INSTALLED AS CLASS 1 DIVISION 1. The important question is does wiring include Receptacles and Switches?2.

Reasonable Interpretation

A reasonable interpretation could be that "wiring" encompasses everything needed to complete the electrical circuits in the classified area, including receptacles and switches. This interpretation aligns with the safety intent of Article 500 and the specific requirements of Article 514.3.

Lack of Specificity in Specifications

The absence of explicit requirements for explosionproof receptacles and switches in the specifications is a problem. It creates a potential error of omission.4.

GFCI and Weatherproof vs. Explosionproof

GFCI protection and weatherproof ratings are not equivalent to explosionproof ratings. Explosionproof equipment is specifically designed to contain an internal explosion and prevent it from propagating to the surrounding atmosphere.

Recommendations & Actions1. RFI (Request for Information) is Mandatory

Immediately submit a formal RFI to the architect and/or engineer of record. Clearly state the ambiguity: "The notes on the plans state that 'ALL WIRING INSTALLED AT FUELING STATION SHALL BE INSTALLED AS CLASS 1 DIVISION 1.' Does this requirement include receptacles and switches located within the Class I, Division 1 areas defined by NEC Article 514?" "The specifications do not explicitly state the requirement for Class I, Division 1-rated (explosionproof) receptacles and switches. Please confirm if these devices must be explosionproof to comply with the plan notes."2.

Document, Document, Document

Keep meticulous records of all communications, RFIs, responses, and any associated costs. This is critical for potential change order negotiations.3.

Review Article 514 (Again)

Carefully review Article 514 of the NEC, especially the diagrams illustrating the classified areas around fuel dispensers. This will help determine if the locations of the receptacles and switches place them within the Class I, Division 1 zone.4.

Consider the Location

Even if outside the typical Article 514 boundaries, are the receptacles and switches in an area subject to the presence of flammable vapors under abnormal conditions? This could still necessitate explosionproof ratings, depending on a formal hazard assessment.5.

Value Engineering (Maybe)

After getting clarification, if explosionproof receptacles and switches are indeed required, explore value engineering options (with the engineer's approval, of course) to minimize the cost impact. Could the receptacles and switches be relocated to an unclassified area?6.

Assume the Most Conservative Interpretation (Until Clarified)

In the absence of clarification, it is prudent to assume the most conservative interpretation, which would be that explosionproof receptacles and switches are required. This protects you from liability and ensures a safe installation.

Who Pays?

This is the tricky part, and it depends on the contract language and the response to your RFI. Engineer Error/Omission

If the engineer confirms that explosionproof receptacles and switches were intended but inadvertently omitted from the specifications, it would likely be considered an error/omission, and they (or their insurance) may be responsible for the additional costs.

Contractor Responsibility

If the engineer argues that the "wiring" note is sufficient, and it's a reasonable interpretation that "wiring" includes the devices in question, the contractor could be responsible. However, the lack of specificity in the specifications weakens this argument.*

Change Order

The most likely outcome is a change order to cover the increased costs. This will involve negotiation between you, the owner, and possibly the engineer. The RFI documentation and your cost records will be essential in this negotiation.

In summary, send the RFI immediately. Don't proceed with purchasing or installing non-explosionproof receptacles and switches until you receive a clear written response from the architect/engineer. Be prepared for a change order negotiation.Disclaimer: This information is for general guidance only and does not constitute legal or professional engineering advice. Consult with qualified professionals for advice tailored to your specific situation. Flag for review