You're right to be concerned about the changes and nuances in equipotential bonding for in-ground pools, especially with the 2020 NEC and the subsequent TIA. Let's break down the situation, specifically focusing on NJ but also providing a broader context.

Understanding the Changes and the Concerns 2020 NEC & Article 680

The 2020 NEC significantly revised Article 680 regarding swimming pools, spas, and similar installations. One of the major changes was related to equipotential bonding. The intent is to minimize voltage gradients in and around the pool, thereby reducing the risk of electric shock.

Equipotential Bonding vs. Grounding

It's crucial to understand the difference. Grounding is for fault current protection, while equipotential bonding is about creating a common voltage plane to minimize voltage differences. Bonding aims to prevent current from flowing through a person because everything they're touching is at the same potential.

The #8 AWG Conductor

The 2020 NEC requires a solid #8 AWG copper bonding conductor to connect various metallic parts within a certain distance of the pool (e.g., reinforcing steel, metal fittings, pump motors, metal structures within 5 feet, etc.). The intent was to provide a more comprehensive bonding system.

The TIA (Tentative Interim Amendment) and Copper Grid Concerns

This is where things get more complex. A TIA indicates that there were perceived problems or ambiguities in the code language. The specific TIA you're referring to likely questioned whether a single #8 AWG conductor was sufficient to create an effective equipotential plane, especially considering the potential for varying soil conditions and the size of the area to be bonded.

Why the Concern? A single #8 AWG conductor might not be enough to effectively "equalize" the potential across a large area. Imagine a large swimming pool deck. If a fault occurs, the voltage potential in one corner might be significantly different than in another corner, even with the #8 AWG conductor. The TIA likely stemmed from concerns that a more robust grid was necessary to truly minimize voltage gradients.

What People Are Actually Doing (NJ Focus and Beyond)

Here's a breakdown of what's happening in practice, considering the code requirements and the TIA concerns:1. Minimum Compliance (Based on 2020 NEC - Before TIA Enforcement)



#8 AWG Loop

Many electricians were initially implementing the minimum requirement, which is running a continuous, unbroken #8 AWG solid copper conductor around the perimeter of the pool, connecting to: Rebar in the pool shell (if present) Metal pool components (ladders, handrails, etc.) Metal components of the pool equipment (pump motor, filter, etc.) Any metal within 5 feet of the inside walls of the pool (light fixtures, fences, etc.)

Understanding Enforcement

It's critical to understand how your specific jurisdiction in NJ is interpreting and enforcing the code. Talk to your local electrical inspector. They have the final say. Some inspectors are strictly adhering to the 2020 NEC as written (with the #8 AWG), while others might be leaning towards a more conservative interpretation due to the TIA.2.

More Robust Solutions (Responding to TIA Concerns and Best Practices)



Copper Grid/Mesh

Some contractors, engineers, and jurisdictions are proactively moving towards a more comprehensive copper grid or mesh system. This involves: Using a grid of bare copper conductors (e.g., #8 AWG or larger) buried under the pool deck and extending at least 3 feet (or more, depending on the design) beyond the pool's edge. Connecting the grid to all the metallic components as described above. This provides a more uniform and effective equipotential plane.

Increased Density of Bonding

Even without a full grid, some are increasing the density of bonding points. Instead of just a single connection to the rebar, they might bond to multiple points.

Engineering Designs

Larger or more complex pool installations often require engineering designs that specify the bonding requirements in detail, going beyond the minimum code.3.

Factors Influencing the Approach



Jurisdictional Interpretation

As mentioned, the biggest variable is how the local electrical inspector interprets the code and addresses the TIA concerns.

Soil Conditions

Soil resistivity plays a role. Highly resistive soil makes it more difficult to create an effective equipotential plane. Some designs might compensate for this with a denser grid or other measures.

Pool Size and Complexity

Larger pools, pools with extensive decks, and pools with complex water features are more likely to require a more robust bonding system.

Risk Tolerance

Some contractors and homeowners prefer to err on the side of caution and install a more robust system, even if it's not strictly required by the local code.

Cost

Of course, cost is a factor. A full copper grid is more expensive than simply running a #8 AWG conductor.

Recommendations and Actions to Take


Talk to Your Local Electrical Inspector (Crucial!)

This is the most important step. Ask them: How they are interpreting the 2020 NEC Article 680 regarding equipotential bonding. Are they taking the TIA into consideration? What specific bonding requirements do they expect for in-ground pools in your area?2.

Review the 2020 NEC Article 680 Thoroughly

Understand the code requirements yourself.3.

Consult with a Qualified Electrical Engineer (Especially for Complex Projects)

An engineer can design a bonding system that is tailored to the specific conditions of your site and meets the code requirements. They can also provide documentation to support the design.4.

Document Everything

Keep detailed records of all bonding connections, materials used, and any inspections performed.5.

Consider a More Robust System (If Feasible)

If you're concerned about safety and the potential for future code changes, consider installing a copper grid or increasing the density of bonding points. It might be a worthwhile investment in peace of mind.6.

Stay Updated

Electrical codes are constantly evolving. Stay informed about any new interpretations, amendments, or code changes that may affect your installation.

Example Scenario

Let's say you're installing an in-ground pool in a town in NJ. You would:1.

Contact the town's electrical inspector. Ask them specifically about their requirements for equipotential bonding of in-ground pools based on the 2020 NEC and any impact the TIA has had.2. Review Article 680 of the 2020 NEC. Make sure you understand the basic requirements.3. Based on the inspector's guidance, you might decide to: Install the minimum #8 AWG loop as described in the 2020 NEC if the inspector allows it. Install a copper grid under the pool deck if the inspector requires it or if you want a more robust system. Increase the density of bonding points along the rebar and other metallic components.

In Summary:

The equipotential bonding requirements for in-ground pools are complex and subject to interpretation. The TIA highlights concerns about the effectiveness of a single #8 AWG conductor. To ensure compliance and safety, it's crucial to communicate with your local electrical inspector, understand the code requirements, and consider a more robust bonding system if necessary. Flag for review