Key Factors to Consider When Determining Propane Tank Placement

When planning for propane tank installation to supply residential appliances and systems, builders, architects, and landscape designers need to consider the logistics of where the tank will be installed. Propane tanks don’t have to disrupt your carefully planned design. There are proven ways to minimize their visual presence and important regulations you must follow.

The first decision is whether to use an above-ground or buried underground tank. Curb appeal and maximizing yard space may be important factors. The next step is to work with the local propane providers to determine tank size needed for the home. The size of the tank should be based on the anticipated load, any future additional load potential, the anticipated lowest ambient temperature, and the vaporization rate of the container. This will then dictate local regulations you must follow, safety guidelines for the tank type, and how the propane servicer will access the tank for deliveries.

For larger developments with multiple homes and shared amenities, a community propane system (CPS) is another option that builders may want to consider. Consult this guide for best practices when planning a CPS for large-scale communities.

Propane: A Safe Bet for Energy Independence

Before we discuss the different tank types and installation factors, it’s important to understand that the tanks themselves are designed and manufactured to withstand weather, a wide range of temperatures, and underground burial while maintaining their safety. In fact, there are still DOT propane tanks in the field that were manufactured in the 1950’s. As long as the container is properly installed and maintained, there is not a limitation on how long it can be in the field.

Propane is a non-toxic fuel that vaporizes at atmospheric pressure when released and will not contaminate soil or groundwater. Propane tanks are typically manufactured from high-grade steel with welded seams, are tested throughout production, and meet manufacturing standards required by the American Society of Mechanical Engineers (ASME), Department of Transportation (DOT), or Transport Canada (TC) for their safety.

Above-Ground Propane Tanks

ASME tanks are large, fixed tanks appropriate for residential or commercial installation with a capacity of 28.6 to 2000+ gallons, although the most common sizes are 120 to 2,000 gallons. DOT and TC cylinders are portable and are measured in pounds of propane they hold. Their capacity is up to 1,000 pounds.
Larger above-ground ASME tanks typically have a horizontal profile and are installed in the yard. For applications with space limitations, there are smaller ASME or DOT containers that can be installed horizontally or vertically, depending on their design, and can be set right up against a structure.

Underground Propane Tanks

Underground tanks have similar capacity, but they are buried under the ground. These tanks have specialized features to ensure safety and prevent corrosion. They work similarly to above-ground tanks, but the earth surrounding the tank provides insulation, protecting it from extreme temperatures and the elements. Underground tanks use protective coatings and cathodic protection to prevent corrosion of the tank’s metal. When a steel propane tank is buried underground, it’s exposed to soil and moisture, which creates an electrochemical cell that leads to corrosion. Cathodic protection is a corrosion prevention technique that makes the tank the cathode of an electrochemical cell by connecting it to a more easily corroded sacrificial metal (usually magnesium) to act as the anode.

Buried tanks are a good option for smaller yards and custom homes as they don’t take up yard space and have a minimal visual impact. While the tank is buried, they have a small dome above ground for access to a riser that contains valves and gauges. That said, the area above the tank should remain clear of everything except landscaping.

Factors in Determining Tank Location

NFPA 58 mandates minimum distance requirements for propane containers from buildings, property lines, entry doors and windows, appliance intake and exhaust terminations, and ignition sources. This reduces fire risk in the rare case of a tank leak or propane release.

Distance from buildings and property lines
Distances are determined by the propane tank size and whether it is an above-ground or underground tank. NFPA 58 also mandates the separation distance between adjacent containers.

• 125- to 500-gallon above-ground propane tanks must be placed at least 10 feet from any building and property line, while containers with less than 125-gallon capacity can be placed next to a building with certain restrictions.
• 1,000- to 2,000-gallon above-ground tanks must be placed at least 25 feet from a building or property line. Under certain circumstances (a single tank of 1,200 gallons or less that is at least 25 feet from any container of more than 125-gallon capacity), that distance can be reduced to 10 feet.
• Underground tanks up to 2,000 gallons must be placed a minimum of 10 feet from buildings and property lines.
• The minimum separation distance between containers with capacities from 251 gallons to 2,000 gallons is 3 feet. That distance is reduced to 0 feet for containers with capacities of 250 gallons or less.

Distance from pressure relief valve to buildings openings
In addition, NFPA 58 mandates the separation distance from a container pressure relief valve and building openings:

• The distance horizontally from the relief valve discharge to an opening below the discharge is 3 feet for cylinders and 5 feet for ASME tanks.
• The distance from the discharge point of a relief valve, vent discharge, and filling connection to exterior source of ignition, openings into direct-vent appliances, and mechanical ventilation air intakes is 5 feet for cylinders that are exchanged, meaning transported full to the customer site to be exchanged with an empty cylinder.
• Cylinders and ASME tanks filled at the point of use must maintain a distance of 10 feet.

Best practices for safe and easy delivery

To ensure propane delivery trucks can safely clear overhead power lines and driveways it’s vital to locate propane tanks according to NFPA 58 rules:
• An aboveground container and any of its parts shall not be located within 6 feet of a vertical plane beneath overhead power lines over 600 volts.
• Combustible material shall not be stored within 10 feet of the container.

Underground tank depth guidelines
NFPA 58 also provides depth guidelines for underground tanks:

• Underground tanks in areas with no vehicular traffic must be buried at least 6 inches below grade.
• Underground tanks within 10 feet of vehicle thoroughfare or parking locations must be at least 18 inches below grade.

The Perfect Propane Tank Location
Finding the perfect propane tank location requires balancing homeowner aesthetic preferences, a property’s space limitations, and regulatory mandates. While following NFPA 58 standards is imperative, you may need to also consider local or region-specific regulations when determining propane tank placement. Check with the local authority having jurisdiction (AHJ), such as the fire marshal, for any local installation requirements. And be sure to work with your local propane supplier when determining tank location, as they or their contractor will likely be installing the tank.