W221 & H221 Preliminary Results

Shipped: April 04, 2022

W221 Preliminary results – Membrane Filtration

Sample NumberOrganismTotal Colony Count - Group Means/Median (cfu/100mL)/MU%
Membrane Filtration Method
Total coliformsThermotolerant coliformsE.coli
W221-1Enterobacter spp.59/59/12.80/0/00/0/0
W221-2E.coli 15/15/29.317/18/36.816/16/28.3
W221-3Enterobacter spp.60/60/15.70/0/00/0/0
W221-4Enterobacter spp.49/50/13.40/0/00/0/0

MU: measure of uncertainty

W221 Preliminary results – Enzyme Substrate

Sample NumberOrganismTotal Colony Count - Group Means/Median (cfu/100mL)
Enzyme Substrate Method
Total coliformsThermotolerant coliformsE.coli
W221-1Enterobacter species59.4/59.40/00/0
W221-2E.coli 14.4/14.913.0/11.613.0/14.1
W221-3Enterobacter species59.8/63.90/00/0
W221-4Enterobacter species49.4/52.50/00/0

W221 Preliminary results – Most Probable Number (MPN)

Sample NumberOrganismTotal Colony Count - Group Means/Median (cfu/100mL)
MPN Method
Total coliformsThermotolerant coliformsE.coli
W221-1Enterobacter species≥23/≥230/00/0
W221-2E.coli 13.4/1214.1/1413.4/12
W221-3Enterobacter species≥23/≥230/00/0
W221-4Enterobacter species≥23/≥230/00/0

W221 Preliminary results – Presence/Absence

Sample NumberOrganismPresence/Absence Method
Total coliformsThermotolerant coliformsE.coli
W221-1Enterobacter species PresentAbsentAbsent
W221-2E.coli PresentPresentPresent
W221-3Enterobacter species PresentAbsentAbsent
W221-4Enterobacter species PresentAbsentAbsent

H221 Preliminary results

SamplesOrganismTotal Colony Count Group Means/MedianMU%
H221-1Enterobacter species55/5815.8
H221-2E.coli293/28521.5
H221-3E.coli62/5819.3
H221-4Enterobacter species59/597.9

MU (%): Measurement Uncertainty in percentage outliers excluded in group means

Posted in critiques, Water Microbiology Results