ASTM D4198-20

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D4198 − 20
Standard Test Methods for
Evaluating Absorbent Pads Used with Membrane Filters for
1
Bacteriological Analysis and Growth
This standard is issued under the fixed designation D4198; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope D3508 Method for Evaluating Water Testing Membrane
3
Filters for Fecal Coliform Recovery (Withdrawn 1995)
1.1 These test methods cover the determination of the
nutrient-holding capacity and the toxic or nutritive effect on
3. Terminology
bacterial growth of organisms retained on a membrane filter,
3.1 Definitions:
when the absorbent pad being tested is used as a nutrient
3.1.1 For definitions of terms used in this standard, refer to
reservoir and medium supply source for the retained bacteria.
Terminology D1129.
1.2 The tests described are conducted on 47 mm diameter
disks, although other size disks may be employed for bacterial
4. Summary of Test Methods
culture techniques.
4.1 Test Method A involves saturating a 47 mm absorbent
1.3 The values stated in SI units are to be regarded as
pad with water and determining the volume of water held by
standard. No other units of measurement are included in this
the pad by weighing the pad dry and when fully saturated.
standard.
4.2 TestMethodBinvolvesculturingmicro-organismsfrom
1.4 This standard does not purport to address all of the
suspensions of pure cultures on a 0.45 µm membrane filter,
safety concerns, if any, associated with its use. It is the
which is placed on the test absorbent pad saturated with the
responsibility of the user of this standard to establish appro-
appropriate growth medium. The resultant cultures are com-
priate safety, health, and environmental practices and deter-
pared to cultures grown on spread plates and to membrane
mine the applicability of regulatory limitations prior to use.
filters placed directly on agar with no absorbent pad.
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
5. Significance and Use
ization established in the Decision on Principles for the
5.1 These test methods are appropriate for qualifying absor-
Development of International Standards, Guides and Recom-
bent pads used with membrane filters for bacteriological
mendations issued by the World Trade Organization Technical
enumeration.
Barriers to Trade (TBT) Committee.
5.1.1 The test methods described are applicable to quality
2. Referenced Documents control testing of absorbent pads by the suppliers and users of
2 these pads and to specification testing of absorbent pads
2.1 ASTM Standards:
intended for use with membrane filters in bacteriological
D1129 Terminology Relating to Water
enumeration.
D1193 Specification for Reagent Water
5.2 Other pure culture organisms and their appropriate
culture medium may be substituted for the E. coli and M-FC
media for specification testing, as required.
6. Apparatus
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These test methods are under the jurisdiction of ASTM Committee D19 on
6.1 Filtration Units for membrane filters with side-arm flask
Water and are the direct responsibilities of Subcommittee D19.08 on Membranes
and tubing.
and Ion Exchange Materials.
Current edition approved Nov. 1, 2020. Published November 2020. Originally
6.2 Vacuum Source.
approved in 1982. Last previous edition approved in 2011 as D4198 – 82 (2011)
which was withdrawn July 2020 and reinstated in November 2020. DOI: 10.1520/
6.3 Vortex Mixer or similar mixer.
D4198-20.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D4198 − 20
6.4 Forceps, flat-bladed. 9.2 M-FC Agar with Rosolic Acid—To a solution of M-FC,
add agar (15 g per 1000 mL), mix while heating in accordance
6.5 Incubator capable of maintaining temperatures of 44.5
with the manufacturer’s instructions, cool, and dispense into
6 0.2 °C.
100 mm petri dishes.
6.6 Stereoscopic Microscope and Illuminator.
10. Culture Preparation
6.7 Illuminated Magnifying Stand for counting colonies on
agar spread plates.
10.1 Resus
...