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Certification
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Leak rate of 0.2 gph with PD = 99.9% and PFA = 0.1% for
Precision Test.
Leak rate of 0.2 gph with PD = 95.0% and PFA = 0.1% for Quick
Test.
Leak rate of 0.1 gph with PD = 95.2% and PFA = 2.5% for 0.1 gph Test
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Leak Threshold
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0.124 gph for leak rate of 0.2 gph, Precision Test.
0.168 gph
for leak rate of 0.2 gph, Quick Test.
0.067 gph for leak rate of 0.1 gph, 0.1
gph Test.
A tank system should not be declared tight if the test result
indicates a loss that equals or exceeds this threshold.
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Applicability
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Gasoline, diesel, aviation fuel, fuel oil #4.
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Tank Capacity
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Maximum of 20,000 gallons.
Tanks less than 95% full may be
tested.
Minimum product level required based on test mode as follows:
For Quick
Test, the minimum product level is computed as probe length multiplied by 0.12
plus 5 inches.
For Precision Test and 0.1 gph Test, the minimum product level is
50% of tank capacity.
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Waiting Time
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Minimum of 1 hour between delivery and testing for Quick Test.
Minimum of 6 hours between delivery and testing for Precision Test and 0.1 gph
Test.
There must be no delivery during waiting time.
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Test Period
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Minimum of 2 hours for all tests.
Test data are acquired and
recorded by system's computer.
Leak rate is calculated from data determined to
be statistically valid.
There must be no dispensing or delivery during test.
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Temperature
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Average for product is determined by a probe with 5 resistance
temperature detectors (RTDs).
The bottom RTD must be submerged in at least 5
inches of product during test.
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Water Sensor
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Must be used to detect water ingress.
Minimum detectable water
level in the tank is 0.874 inch.
Minimum detectable water level change is 0.011
inch.
System is default programmed to report a water depth only when it exceeds
3.5 inches.
System can be programmed to report a water depth of 0.874 inch and
above.
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Calibration
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System must be checked and, if necessary, calibrated in
accordance with manufacturer's instructions.
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Comments
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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.
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.
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