Okay, let's break down the requirements for your situation.

Understanding the Requirements Hazardous Locations

You're correct that the area within 20 feet horizontally of gasoline dispensing units and their electrical enclosures is generally classified as Class I, Division 2. This classification triggers specific requirements for wiring methods.

MC-HL Cable

Using MC-HL cable with a gas/vaportight continuous sheath is a good starting point. MC-HL cable can be suitable for hazardous locations, but it must be installed correctly.

Sealing Fittings (Explosion Proof)

This is the critical question. Do you need explosion-proof sealing fittings?

The Answer: Likely Yes, BUT it Depends on the Listing of the MC-HL Cable and Connectors

Here's the reasoning:1. NEC 501.15(B) (2023) (Sealing, Class I, Division 2)

The NEC (National Electrical Code) generally requires sealing fittings to prevent the passage of gases, vapors, or flames from one portion of the electrical system to another. In Class I, Division 2 locations, sealing is required under specific conditions.2.

MC Cable Sealing Requirements

If the MC-HL cable is NOT listed as intrinsically safe or nonincendive, it MUST be sealed at the point where it enters the enclosure.3.

MC-HL Connectors

The NEC Article 330.15 specifies that "MC cable shall be supported and secured at intervals not exceeding 6 ft." In addition, connections and fittings used with Type MC cable shall be identified for use with the cable and shall be installed in accordance with the instructions provided with the fitting or connector.
4.

Specific Approval and Listing are Key

You can't just use any connector with MC-HL cable in a hazardous location. The connector

must be specifically listed and approved for use with the specific MC-HL cable you are using and listed for use in Class I, Division 2 locations. These connectors are often described as "hazardous location connectors" or "explosion-proof connectors" or "intrinsically safe"5. Listing Information is Crucial

Review the MC-HL cable manufacturer's documentation and the connector manufacturer's documentation very carefully. Look for specific statements about compliance with Class I, Division 2 requirements and the listing standards (e.g., UL, CSA). The listing information will define the exact acceptable installation methods, including whether sealing is required.

Here's a more structured approach to determine your exact need


Identify Your Specific MC-HL Cable

Get the exact manufacturer and part number of the MC-HL cable you are planning to use.2.

Consult the Cable Manufacturer's Documentation

Does the documentation explicitly state that the cable is suitable for Class I, Division 2 locations? Does it specify any limitations or special installation requirements for hazardous locations? Does it mention specific connector types that are required?3.

Identify Potential Connectors

Find connectors that are compatible with your MC-HL cable.4.

Consult the Connector Manufacturer's Documentation

Does the connector documentation explicitly state that it is suitable for use in Class I, Division 2 locations with the specific MC-HL cable you are using? Is the connector listed for use in hazardous locations (e.g., UL 1203)? Does the documentation specify that the connector provides a seal against gas/vapor intrusion? Does the documentation state "intrinsically safe"?5.

If the Cable and Connector are Approved for Class I, Div. 2

Carefully follow the manufacturer's installation instructions. Correct installation is crucial for maintaining the integrity of the hazardous location rating.6.

If the Cable and Connector do not have explicit Class I, Div. 2 approval

You will likely need to use a separate, explosion-proof sealing fitting in addition to the standard MC-HL connector at the point where the cable enters the enclosure. This sealing fitting must be appropriate for Class I, Division 2.

Important Considerations



Local AHJ (Authority Having Jurisdiction)

Ultimately, the AHJ (typically the local electrical inspector) has the final say on whether your installation meets code requirements. Discuss your plans with them before you begin the installation to avoid costly rework.

Qualified Personnel

Hazardous location installations should only be performed by qualified electricians who are experienced in working in these environments.

Grounding

Proper grounding is essential in hazardous locations. Ensure that the MC-HL cable is properly grounded according to the NEC and the manufacturer's instructions.

Double-Check Classifications

Ensure that your understanding of the area classification is correct. If there is any doubt, consult with a qualified hazardous location consultant.

In Summary:

While MC-HL cable offers a good level of protection, simply using it does not automatically guarantee compliance with hazardous location requirements. The listing of the cable and connectors, along with proper installation according to the manufacturer's instructions, are paramount. It is very likely that you will* need sealing fittings or connectors specifically listed for Class I, Division 2, but this is dependent on the specific cable and connectors you choose. Consulting the manufacturer's documentation and your local AHJ is essential. Flag for review