The tracer wire shall not be less than ______ and be suitable for direct burial.

The standard for tracer wire requires it to be no less than 18 AWG (American Wire Gauge) to ensure adequate strength and conductivity for underground applications. This gauge is specifically designed to provide an effective means for locating underground utilities, which is essential for avoiding damage during excavation activities.

Using 18 AWG as a minimum thickness ensures that the wire is robust enough to withstand the conditions it will face when buried, including soil pressure, moisture, and potential abrasion. Thinner wires, such as 20 AWG or 22 AWG, may not provide sufficient durability or electrical conductivity in these environments, potentially leading to failure in locating the underground infrastructure, which can be a major safety and operational risk.

Moreover, 16 AWG is thicker than the minimum requirement, and while it can be used effectively, the minimum standard is set at 18 AWG for balance between strength and practicality. Therefore, the requirement of 18 AWG establishes a baseline for safe and effective use in direct burial situations, reinforcing best practices in plumbing and utility installations.