LP-Gas Container Separation Check
Whether an LP-gas container sits far enough from the things it has to sit away from.
Example
You enter
- Container water capacity (gal) 500
- Required to the building (ft) 10
- Required to the property line (ft, 0 to skip) 10
- Required to a source of ignition (ft, 0 to skip) 10
- Required to an opening (ft, 0 to skip) 5
- Measured to the building (ft) 12
- Measured to the property line (ft, 0 to skip) 14
- Measured to a source of ignition (ft, 0 to skip) 18
- Measured to an opening (ft, 0 to skip) 6
- Next container size: required to the building (ft, 0 to skip) 25
- Relief discharge directed at an opening no
You get
- Building margin (ft) 2.0
- Property line margin (ft) 4
- Ignition margin (ft) 8
- Opening margin (ft) 1.0
- Longest requirement (ft) 10.0
- Next size up short by 13.0 ft
Details, formula, and sources
The NFPA 58 distances are tabulated by container water capacity and are not reproduced here -- the adopted edition governs and the required figures are entered -- so what this does is the comparison: each measured distance against its requirement, with the margin and a pass or fail per element. THE DISTANCES STEP RATHER THAN SCALE. They change at capacity breakpoints, so the choice between one container size and the next is not only a capacity decision: it can move the tank across the yard. Checking the separation for both candidate sizes before choosing is the cheap version of that conversation, and it is the one that stops a customer being told they can double their capacity in a yard that will not take it. THE CLEARANCE PEOPLE FORGET IS NOT TO THE WALL BUT TO OPENINGS. The relief valve discharge has to be clear of windows, doors and any opening into a below-grade space, because propane is heavier than air and will find a basement window well and stay in it. That is a DIRECTIONAL requirement -- where the relief points matters, not only how far the container sits -- and no horizontal measurement addresses it, which is why it is flagged separately here. THE OTHER QUIET ONE IS THE POINT OF TRANSFER. The place the delivery hose connects carries its own separation requirements, frequently more restrictive than the container's own, so a tank that complies while the truck is absent can be non-compliant while it is being filled. AND TWO SMALLER CONTAINERS MANIFOLDED may be treated differently from one large one; manifolding also adds wetted area and therefore vaporization capacity, so it is a real option rather than a workaround. This compares entered distances against entered requirements. It does not reproduce or look up any separation table, determine which edition or amendments apply, address underground or mounded containers, which have their own and generally shorter distances, evaluate the point of transfer, the filling connection or the dispensing arrangement, address clearances to driveways, combustible materials or vegetation, or determine what any standard requires. NFPA 58 as adopted, the AHJ, and the container and system installer govern.
each measured distance compared against the requirement entered for it, with the margin and a pass or fail per element, plus the same building check at the next container size.
The NFPA 58 separation tables are NOT reproduced: they are indexed by container water capacity, they step at capacity breakpoints, and the adopted edition and its amendments govern.
Comparisons only; no table is reproduced.
Estimate. AHJ and licensed professional govern.
Field names used by the API: water_capacity_gal, required_building_ft, required_property_line_ft, required_ignition_ft, required_opening_ft, measured_building_ft, measured_property_line_ft, measured_ignition_ft, measured_opening_ft, next_size_required_building_ft, relief_points_at_opening, building_margin_ft, property_line_margin_ft, ignition_margin_ft, opening_margin_ft, governing_required_ft, next_size_shortfall_ft
- Requirements are entered no separation table is reproduced or looked upNFPA 58 as adopted
- Aboveground containers underground and mounded containers have their own, generally shorter distancesNFPA 58 as adopted
- Relief direction is a flag, not a distance no horizontal measurement addresses itthe AHJ