How must a non-interchangeable underground container be protected from vehicular damage where traffic is expected?

The requirement for a non-interchangeable underground liquefied petroleum gas container to be protected from vehicular damage, especially in areas where traffic is expected, is critical for safety and compliance with NFPA 58. The standard specifies that such containers must be buried at least 18 inches below the ground surface. This depth is designed to shield the container from impacts caused by vehicles while also providing adequate coverage to minimize the risk of corrosion or other environmental degradation.

The specification for 18 inches indicates a balance between safety, practicality, and cost. Going deeper than this can complicate installation and maintenance, while providing insufficient cover can expose the container to potential damage from larger vehicles. Thus, adherence to the 18-inch requirement ensures that the container is adequately protected in typical traffic scenarios, mitigating risks associated with vehicular accidents. This standard reflects the need for safety measures in locations where the likelihood of vehicles interacting with buried containers is higher.