4
9
A.1
Aviation kerosene, other middle distillate fuels and gasoline.
A.1.1 Immediately prior to testing, shake the sample for 30 seconds. If fuel samples contain
visible free water, the sample should be allowed to stand for 12 minutes to enable water to
settle from the sample to be tested. For consistency, it may be advisable to apply this
settling time for all fuel samples even if free water is not observed.
A.1.2 Remove the cap of the MicrobMonitor2 test bottle taking care not to touch the inside
and place it on a clean surface.
A.1.3 Open the peel pack containing a syringe at the handle end and remove the
syringe taking care not to touch the lower barrel and nozzle.
A.1.4 Using the syringe, draw fuel from approximately 3 cm below the surface of the
sample. If there is less than 6 cm depth of fuel phase, draw sample from approximately
halfway down the fuel phase. Avoid the transfer of visible interfacial particulate, water
droplets or emulsion in the aliquot to be tested.
A.1.5 Draw fuel into the syringe until it is more than half full and then, with the syringe nozzle
uppermost, press the plunger to expel air. Expel surplus fuel until the end of the plunger
aligns with the mark for the required volume of sample (see table 1).
A.1.6 Insert the tip of the syringe into the neck of the MicrobMonitor2 test bottle and
dispense the sample by fully depressing the syringe plunger.
A.1.7 Replace the cap on the MicrobMonitor2 bottle and tighten. Record the sample
details and test date on the label provided and stick it on a narrow side of the bottle.
Proceed to step B.
TEST PROCEDURE
A. Add
sample
to
the
MICROBMONITOR
2
®
test bottle.
Follow the appropriate steps below to add distillate fuel or biofuel (A.1), heavy/residual fuel or oil (A.2), water (A.3)
or surfaces deposits (A.4) to the MicrobMonitor2 test bottle.
MICROBMONITOR
2
®
Test Results Chart
Appearance after incubation
N
umber
of colonies in
test bottle
(counted or estimated)
Volume tested
Microbial Content of
Sample
None
0.5 ml of fuel (syringe)
<2000 CFU per litre
0.25 ml of fuel (syringe)
<4000 CFU per litre
0.1 ml of water (syringe)
<10 CFU per ml
0.01 ml of water or oil
(loop dispenser)
<100 CFU per ml
10 Colonies
If possible, count the exact
number of colonies and
calculate the actual number
of CFU present in the sample
0.5 ml of fuel (syringe)
2 x 10
4
CFU per litre
0.25 ml of fuel (syringe)
4 x 10
4
CFU per litre
0.1 ml of water (syringe)
100
CFU per ml
0.01 ml of water or oil
(loop dispenser)
1000 CFU per ml
100 Colonies
If possible, count the exact
number of colonies and
calculate the actual number
of CFU present in the sample
or
Estimate 100 colonies if
result is similar to picture
0.5 ml of fuel (syringe)
c. 10
5
CFU per litre
0.25 ml of fuel (syringe)
c. 10
5
CFU per litre
0.1 ml of water (syringe)
c. 10
3
CFU per ml
0.01 ml of water or oil
(loop dispenser)
c. 10
4
CFU per ml
Estimate 1000 colonies if
result is similar to picture
0.5 ml of fuel (syringe)
c. 10
6
CFU per litre
0.25 ml of fuel (syringe)
c. 10
6
CFU per litre
0.1 ml of water (syringe)
c.10
4
CFU per ml
0.01 ml of water or oil
(loop dispenser)
c.10
5
CFU per ml
Estimate 10,000 or more
colonies if result similar to
picture
0.5 ml of fuel (syringe)
c.10
7
CFU per litre or
above
0.25 ml of fuel (syringe)
c.10
7
CFU per litre or
above
0.1 ml of water (syringe) c.10
5
CFU per ml or above
0.01 ml of water or oil
(loop dispenser)
c.10
6
CFU per ml or above
MICROBMONITOR
2
®
T R U S T E D
I N N O V A T I V E
A C C U R A T E
D E P E N D A B L E
+
+
+
Results that count
