Certification

Leak rate of 0.1 gph with PD = 99% and PFA = 1% for Precision Test. 
Leak rate of 0.1 gph with PD = 96% and PFA = 4% for Quick Test.

Leak Threshold

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

Applicability

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

Tank Capacity

Maximum of 15,000 gallons. Tanks less than 95% full may be tested. Minimum product level required based on tank diameter as follows:
48" dia/min 8.5"; 
64" dia/min 10.5"; 
72" dia/min 11.5"; 
96" dia/min 14"; 
126" dia/min 18". 
For other tank diameters, see evaluation report.

Waiting Time

Minimum of 6 hours between delivery and testing. 
None between dispensing and testing. 
There must be no delivery during waiting time.

Test Period

Minimum of 3 hours, 45 minutes for Precision Test. 
Average of 3 hours 45 minutes at 95% full and 5 hours 58 minutes at 50% full during Precision Test evaluation. Minimum of 1 hour, 49 minutes for Quick Test. 
Average of 1 hour 48 minutes at 95% full and 2 hours 48 minutes at 50% full during Quick Test evaluation. 
Test data are acquired and recorded by a microprocessor which automatically determines test time based on tank size and product level. 
There must be no dispensing or delivery during test.

Temperature

Probe contains 5 resistance temperature detectors (RTDs) to monitor average product temperature. 
At least one RTD must be submerged in product during test.

Water Sensor

Must be used to detect water ingress. 
Minimum detectable water level in the tank is 0.66 inches. 
Minimum detectable change in water level is 0.039 inches.

Calibration

RTDs and 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. 
Tests only the 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 which routinely contains product.

OPW Fuel Management Systems       

Evaluator:  Midwest Research Institute

6900 Santa Fe Dr.

Tel:  (816) 753-7600

Hodgkins, IL 60525

Dates of Evaluation:  02/08/94, 09/19/97             

Tel: (708) 485-4200

01/04/00