Line tightness testing.
Pressure-decay tightness testing on every product line under EPA 40 CFR 280.41. Inconclusive results are common, so we isolate and verify before declaring a leak.
Manufacturer-certified · EPA 40 CFR Part 280 · Testing tanks since 1997
Pressure-decay tightness testing on every pressurized product line at a UST site.
How we run it.
PTTI uses the Estabrook line tightness tester with a nitrogen tank. The line is pressurized to 1.5 times its operating pressure. There is no fixed pressure target; the test pressure is calculated per line.
Pressure is held and decay is monitored over time. A failed reading does not always mean a line leak. Inconclusive testing is common, because many components in the line system can mimic a leak signature.
When a reading indicates failure, PTTI isolates at the ball valve or check valve in the STP. If those components are not holding, a silver bullet is installed for further isolation before the check valve. From there, PTTI determines whether the failure is the line or another piece of equipment. We do not declare a line leak until absolutely certain.
- Equipment
- Estabrook line tightness tester with a nitrogen tank. Silver bullet isolation device.
- Frequency
- On the schedule your state's UST program requires. PTTI typically runs the line tightness test and the leak detector certification on the same visit.
- Deliverable
- An audit-ready line tightness record for every line tested, sent to you after the visit and formatted for your state compliance file. PTTI prepares the record; your operator files it with the state.
What we look for.
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1
Inconclusive testing
The most common pattern. A pressure reading indicates a failure even though the line itself may be sound. PTTI isolates and re-tests before declaring a line leak.
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2
Ball valve at the STP not holding
The ball valve in the submersible turbine pump does not seat, so the isolated section will not hold pressure and can mimic a line leak.
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3
Check valve not holding
A check valve that does not seal looks like a line failure on the gauge. PTTI installs a silver bullet to isolate past it and tell an equipment failure from a true line leak.
Frequently asked.
What does "inconclusive testing" mean?
A pressure reading can indicate a failure even when the line itself is sound, because a ball valve, check valve, or other component in the system can mimic a leak signature. When that happens PTTI isolates the suspect components and re-tests before concluding anything. We do not declare a line leak until we are certain.
What is a silver bullet, and when do you use it?
A silver bullet is an isolation device PTTI installs before the check valve when a reading is inconclusive. It lets the technician isolate further along the line so a true line failure can be told apart from an equipment failure at the STP.
How often is line tightness testing required?
Line tightness scheduling depends on your state's UST program and how your release detection is configured. PTTI typically runs the line tightness test and the leak detector certification on the same visit.