Certification
|
Leak
rate of 0.2 gph with PD = 100% and PFA = 0%.
|
Leak
Threshold
|
Not
applicable for qualitative methods.
Method is qualitative and reports a result of “pass” or
“fail”.
|
Applicability
|
Gasoline,
diesel, aviation fuel, solvents, waste oil, fuel oil #4,
water.
Other liquids with known coefficients of expansion and
density may be tested after consultation with the manufacturer.
|
Tank
Capacity
|
Maximum
of 18,000 gallons for single tanks
Maximum of 54,000 gallons cumulative capacity for manifolded
tank systems.
Minimum product level required to conduct a test is 20
inches.
|
Throughput
|
Monthly
maximum of 147,136 gallons.
|
Waiting
Time
|
Minimum
of 4 hours stabilization time is allowed between delivery
and data collection.
|
Test
Period
|
Data
collection time ranges from 3 to 27 days.
Data sampling frequency is every 1 minute.
System collects data at naturally occurring product levels
without interfering with normal tank operation, and discards
data from unstable periods when system performs test.
|
Temperature
|
Average
for product is determined by a minimum of 5 sensors.
|
Water
Sensor
|
Must
be used to detect water ingress.
Minimum detectable water level in the tank is 0.736 inch.
Minimum detectable change in water level is 0.031 inch.
|
Calibration
|
Probe
must be checked annually and, if necessary, calibrated
in accordance with manufacturer's instructions.
|
Comments
|
Evaluated using both single
and manifolded tank systems with probes in each tank.
For valid monthly testing, a conclusive test report must
be produced for each tank every month. System warns operator
if there are no “ passing” tests completed during the
month. For very active tanks, a tank shut down may become
necessary in order for the system to collect enough quiet-time
data for a test.
Constant and variable leaks were mathematically induced
into tight tank test records, which were collected by
systems installed at various active tank sites.
The database for evaluation of the system included sites
with vapor recovery and blending dispensers. Tanks used
in this evaluation contained gasoline and diesel.
|