Overfill Prevention Verification
Flapper valves, ball float valves, and overfill alarms under EPA 40 CFR 280.35. PEI RP1200 C-5 and C-6 forms, every device type present tested.
Manufacturer-certified · Testing UST & AST systems since 1997 · Serving 13 states and expanding
Three EPA-recognized overfill prevention device types: flapper valves (shutoff at 95% capacity), ball float valves (restrict at 90% capacity), and overfill alarms (alert at 90% capacity).
Testing Method
Overfill prevention testing follows PEI RP1200 Section 7. Each device type present at the site is tested.
Flapper valves: remove the drop tube, visually inspect the shutoff valve and float mechanism, manually move the float to confirm free movement, and use the manufacturer’s procedure to verify shutoff at no more than 95% tank capacity. Ball float valves: remove the ball float assembly, inspect the ball and cage for damage, cracks, and corrosion, check the vent orifice for clear flow, and verify flow restriction at no more than 90% capacity.
Overfill alarms: compare the ATG console reading to a gauge stick, verify the alarm setting is at no more than 90% full, move the fuel float upward until the overfill alarm triggers, and measure the distance to calculate the percent-full at trigger.
- Equipment
- Drop-tube removal tools. Tape measure or gauge stick. ATG probe access tools.
- Frequency
- For regulated UST systems, at least once every three years under the federal periodic-inspection framework, with additional requirements as applicable.
- Deliverable
- A record of the overfill devices inspected, checks performed, and results.
Common Overfill Device Failure Modes
-
1
Flapper Valve Disabled, Damaged, or Missing Float
-
2
Ball Float Cage Corrosion
Metal seats or balls corrode or deform; the vent orifice clogs.
-
3
Alarm Console Programming Drift
The console-programmed value disagrees with the measured trigger point.
Overfill Prevention Testing, frequently asked.
How often does overfill prevention need testing?
Every three years, per device type present at the site, under EPA 40 CFR 280.35. PTTI bundles it with the rest of the containment-tier testing where the cycles line up.
What is the difference between a flapper valve and a ball float valve?
The ball float valve restricts airflow in the vapor path while the tank is being filled. The flapper valve is in the fill path and stops product from entering the tank.
Can ball float valves still be used?
Existing-device eligibility depends on the installation and applicable requirements. Vent-line flow restrictors cannot meet the federal overfill requirement when that equipment is installed or replaced after October 13, 2015.