Certification

Leak rate is 0.2 gph with PD = 96.9% and PFA = 3.1%
 

Leak Threshold

0.1 gph. 
A tank system should not be declared tight if the test result indicates a loss or gain that equals or exceeds this threshold.

Applicability

Gasoline, diesel, aviation fuel, fuel oil #4. 

Tank Capacity

Maximum of 76,500 gallons.

Tank must be between 50 and 95% full.

Waiting Time

Minimum of 12 hours between delivery and testing.

There must be no delivery or dispensing during waiting time.

Test Period

Minimum of 24 hours. 

Test data are acquired and recorded by system's computer.
There must be no dispensing or delivery during test.

Temperature

Average for product is determined by 5 or more thermistors.

Water Sensor

Must be used to detect water ingress.

Minimum detectable water level in the tank is 0.52 inch.

Minimum detectable change in water level is 0.032 inch

Calibration

Probe must be checked and, if necessary, calibrated in accordance with manufacturer's instructions.

Comments

Not evaluated using manifolded tank systems.  Therefore, this certification is only applicable when there is a probe used in each tank and the siphon is broken during testing. 
Operates on buoyancy principle which employs a servo gauge.

Evaluated in a 51,000 gallon horizontal underground tank, 13 feet diameter by 54 feet long.
Tests only portion of tank containing product.

As product level is lowered, leak rate in a leaking tank decreases (due to lower head pressure).

consistent testing at low levels could allow a leak to remain undetected.

EPA leak detection regulations require testing of the portion of the tank system which routinely contains product.