AS 4276.7-1995

1 - AS 4276.7-1995 WATER MICROBIOLOGY - THERMOTOLERANT COLIFORMS AND ESCHERICHIA COLI-MEMBRANE FILTRATION METHOD
1 - PREFACE
1 - METHOD
1 - 1 SCOPE
1 - 2 REFERENCED DOCUMENTS
1 - 3 CULTURE MEDIA AND REAGENT
1 - 3.1 Membrane lauryl sulfate (MLS) agar
1 - 3.2 Membrane lauryl sulfate (MLS) broth
1 - 3.3 EC broth
2 - 3.4 Tryptone water
2 - 3.5 Indole reagent (Kovacs’)
2 - 4 APPARATUS
2 - 4.1 Apparatus and materials for membrane filtration
2 - 4.2 Incubators or water baths
2 - 5 REFERENCE CULTURES
2 - 5.1 Escherichia coli, NCTC 9001 or ATCC 11775 or ACM 1803
2 - 5.2 Enterobacter aerogenes, NCTC 10006 or ATCC 13048 or ACM 1976
2 - 5.3 Use of reference cultures
2 - 6 SAMPLES
2 - 6.1 Laboratory samples
2 - 6.2 Dilutions
2 - 7 PROCEDURE
2 - 7.1 Preparation of plates or pads
2 - 7.2 Controls
2 - 7.3 Filtration procedure
2 - 7.4 Resuscitation and incubation
2 - 7.5 Identification of presumptive thermotolerant coliforms and E. coli
3 - 7.6 Confirmatory tests
3 - 7.7 Interpretation of results
3 - 7.7.1 Confirmed thermotolerant coliforms
3 - 7.7.2 Confirmed E. coli
3 - 7.7.3 Further testing
3 - 8 TEST REPORT
4 - 9 REFERENCE
5 - APPENDIX A - FLOW DIAGRAM FOR THERMOTOLERANT COLIFORMS AND E. COLI-MEMBRANE FILTRATION METHOD

This Standard sets out a method, using membrane filtration, for enumerating thermotolerant coliforms and Escherichia coli in water.

This Standard sets out a method, using membrane filtration, for enumerating thermotolerant coliforms and Escherichia coli in water.NOTES:1 Thermotolerant coliforms are often also referred to as 'faecal coliforms' although the organisms may not be of faecal origin.2 Membrane filtration is suitable for enumerating microorganisms only when the turbidity of the water is low.3 Bacterial counts derived from membranes with fewer than 20 or more than 80 thermotolerant coliform colonies are approximate.4 A flow diagram of the procedure is shown in Appendix A.

First published as AS 1095.4.1.6-1981.
Revised and redesignated AS 4276.7-1995.