Why Inspections Exist
The LP gas installation inspection is not bureaucratic box-checking. Propane is stored at high pressure and is heavier than air — it accumulates in low spots if it leaks, creating a fire and explosion risk that is not always visible or odor-detectable at low concentrations. The inspection verifies that your installation meets the engineering standards designed to prevent ignition scenarios and ensure your system operates safely for decades.
Understanding what the inspector is looking for also helps you ensure your licensed contractor has done the job correctly before the inspector arrives. A failed inspection requires rescheduling, delays your first fill, and may cost additional contractor time.
Above-Ground Tank Final Inspection Checklist
1. Setback Distances
The inspector will measure — with their own tape measure — the distance from the tank's outer shell to building walls, windows, doors and other openings, the electric meter and electrical panel, any AC condenser units or other ignition sources, and the property line. NFPA 58 minimums for tanks under 500 gallons: 10 feet from all of these. For tanks 500–2,000 gallons: 25 feet. If any measurement falls short, the installation fails and the tank must be relocated before re-inspection.
2. Tank Placement and Surface
The tank must sit on a stable, level surface. Acceptable surfaces include a concrete pad, compacted gravel, or firm native soil. The tank may not be placed on loose soil that could shift or settle, on wooden decking, or against any building wall. The area under and around the tank must be free of combustible material (leaves, mulch, dry vegetation).
3. Labeling and Signage
NFPA 58 requires specific labels on and near a propane tank:
- "LP GAS" or "PROPANE" on the tank body
- "FLAMMABLE" marking
- Tank capacity in gallons, visible from the fill connection side
- The service valve must be labeled
- Many jurisdictions also require a "NO SMOKING WITHIN 25 FEET" sign near the fill connection
4. Service Shutoff Valve
A manually operable service shutoff valve must be accessible at the tank — not buried in a cabinet or blocked by other equipment. The inspector will operate the valve to confirm it functions. Emergency responders need to be able to shut off gas at the tank without tools in an emergency.
5. First-Stage Pressure Regulator
The first-stage regulator attached to the tank outlet must be properly sized for the home's gas demand, correctly oriented (not inverted or angled in a way that allows water intrusion), and equipped with a vent limiter if required by local code. Regulator sizing and installation are typically performed and verified by the licensed contractor before inspection.
6. Supply Line Connection and Materials
The gas supply line from the tank to the home must use code-approved materials. Buried sections require specific pipe materials and burial depth (typically 12–18 inches below grade minimum, deeper in frost-prone areas). The inspector checks that connections at the tank are made with approved fittings and that there are no visible signs of improper improvised connections.
7. Pressure Test
The gas piping system — from the tank outlet through all supply lines to the first shutoff at each appliance — is pressure-tested before the tank is filled. The test applies compressed air or inert gas to the system and verifies it holds pressure for a specified duration without drop. Your licensed contractor performs this test. The inspector may require a witnessed test or request the test report documentation. Any pressure drop indicates a leak that must be found and repaired before passing inspection.
8. Guard Posts (If Required)
If the tank is located where a vehicle could make contact — near a driveway, in a parking area, or within 10 feet of a road — steel guard posts (bollards) are required. The inspector verifies that guard posts are present, properly installed in concrete footings, and positioned to deflect a vehicle impact away from the tank. A tank without required guard posts is a failed inspection.
9. Flood Zone Anchoring (If Applicable)
For properties in FEMA-designated flood zones, above-ground tanks must be anchored to resist flotation and lateral movement during a flood event. Anchoring typically consists of steel straps or chains secured to a concrete deadman anchor or ground anchors. The inspector verifies anchoring hardware is installed and the documentation of the anchor specification is on file.
Additional Checks for Underground Tanks
Pre-Backfill Inspection Items
For underground installations, the inspector visits the site before the excavation is filled in — when the tank is still fully visible and accessible. They verify:
- Tank depth: top of tank at least 6 inches below finish grade
- Bedding material: clean sand or pea gravel below and around the tank per specifications
- Cathodic protection anodes: correctly attached and positioned per manufacturer specifications
- Vent pipe routing: correctly installed and temporarily supported
- Fill connection and gauge access: positioned to remain accessible above grade after backfill
- Setback distances: measured from the excavation edges to all required features
Final Inspection Items (Underground)
After backfill, the final inspection verifies:
- Vent pipe termination: at least 5 feet above grade, at least 5 feet from any building opening
- Fill connection and gauge: accessible, labeled, and properly capped
- Surface restoration: completed and stable
- Cathodic protection documentation: initial test documentation filed with the permit
- Supply line connection and pressure test: same as above-ground requirements
Most Common Inspection Failures
| Failure Reason | How to Prevent It |
|---|---|
| Setback too short from AC unit | Measure from tank to AC unit before installer leaves — many forget this one |
| Missing required guard posts | Confirm with inspector in advance whether your location requires them |
| Pressure test failure (piping leak) | Pressure test must be completed and passing before inspector arrives |
| Missing labeling on tank | Confirm tank arrived with full factory labels; replace any that are missing |
| Underground: backfill before inspection | Schedule pre-backfill inspection before covering — do not proceed without approval |
| Regulator incorrectly oriented | Contractor responsibility; verify before inspector arrives |
| Missing flood anchoring in flood zone | Check FEMA flood zone map early; design anchoring before installation day |
How to Schedule Your Inspection
Call your county building or fire department as soon as your installation is scheduled. For above-ground tanks, schedule the final inspection for the day after installation is complete. For underground tanks, schedule the pre-backfill inspection for installation day — the inspector must see the tank before any backfill begins. In busy jurisdictions, inspectors may be booked 3–5 days out, so call early.
When scheduling, provide: your permit number, the property address, the type of inspection (above-ground final, underground pre-backfill, underground final), and your preferred date and time window. Most jurisdictions give a half-day window (morning or afternoon) rather than a specific time.
Yes, and it is recommended. Being present at the inspection allows you to hear any concerns directly from the inspector, ask questions, and understand what passed and what (if anything) needs correction. Your licensed contractor should also be present or available by phone. If the inspection passes, the inspector signs off on the permit card (or in the digital system) and you can proceed with the first fill. If it fails, you will receive a written or digital correction notice listing what must be addressed before re-inspection.
A failed inspection results in a correction notice identifying specific items that do not comply with code. Your licensed contractor corrects the deficiencies and you request a re-inspection. Re-inspection fees vary by jurisdiction — some are free for the first re-inspection, others charge $25–$75. Common corrections (like repositioning the tank to improve a setback or adding a missing guard post) can often be completed same-day. More significant issues (a failed pressure test requiring the contractor to find and repair a leak in buried piping) may take several days. Do not fill or use the tank until the inspection is passed and the permit is closed.