ASTM D4198-82(2003)

Standard Test Methods for Evaluating Absorbent Pads Used with Membrane Filters for Bacteriological Analysis and Growth

SIGNIFICANCE AND USE
These test methods are appropriate for qualifying absorbent pads used with membrane filters for bacteriological enumeration.
5.1.1 The test methods described are applicable to quality control testing of absorbent pads by the suppliers and users of these pads and to specification testing of absorbent pads intended for use with membrane filters in bacteriological enumeration.
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.
SCOPE
1.1 These test methods cover the determination of the nutrient-holding capacity and the toxic or nutritive effect on bacterial growth of organisms retained on a membrane filter, when the absorbent pad being tested is used as a nutrient reservoir and medium supply source for the retained bacteria.  
1.2 The tests described are conducted on 47-mm diameter disks, although other size disks may be employed for bacterial culture techniques.  
1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 28-Oct-1982
• ICS: 07.100.10 - Medical microbiology
• Technical Committee: D19 - Water
• Drafting Committee: D19.08 - Membranes and Ion Exchange Materials

Relations

• Replaces: ASTM D4198-82(1998) - Standard Test Methods for Evaluating Absorbent Pads Used with Membrane Filters for Bacteriological Analysis and Growth
• Effective Date: 29-Oct-1982

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D4198–82(Reapproved2003)
Standard Test Methods for
Evaluating Absorbent Pads Used with Membrane Filters for
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 appropriate growth medium. The resultant cultures are com-
pared to cultures grown on spread plates and to membrane
1.1 These test methods cover the determination of the
filters placed directly on agar with no absorbent pad.
nutrient-holding capacity and the toxic or nutritive effect on
bacterial growth of organisms retained on a membrane filter,
5. Significance and Use
when the absorbent pad being tested is used as a nutrient
5.1 These test methods are appropriate for qualifying absor-
reservoir and medium supply source for the retained bacteria.
bent pads used with membrane filters for bacteriological
1.2 The tests described are conducted on 47-mm diameter
enumeration.
disks, although other size disks may be employed for bacterial
5.1.1 The test methods described are applicable to quality
culture techniques.
control testing of absorbent pads by the suppliers and users of
1.3 This standard does not purport to address all of the
these pads and to specification testing of absorbent pads
safety concerns, if any, associated with its use. It is the
intended for use with membrane filters in bacteriological
responsibility of the user of this standard to establish appro-
enumeration.
priate safety and health practices and determine the applica-
5.2 Other pure culture organisms and their appropriate
bility of regulatory limitations prior to use.
culture medium may be substituted for the E. coli and M-FC
2. Referenced Documents media for specification testing, as required.
2.1 ASTM Standards:
6. Apparatus
D1129 Terminology Relating to Water
6.1 Filtration Units for membrane filters with side-arm
D1193 Specification for Reagent Water
flask and tubing.
D3508 Method for Evaluating Water Testing Membrane
3 6.2 Vacuum Source.
Filters for Fecal Coliform Recovery (Discontinued 1994)
6.3 Vortex Mixer or similar mixer.
3. Terminology 6.4 Forceps, flat-bladed.
6.5 Incubator capable of maintaining temperatures of 44.5
3.1 Definitions—For definitions of terms used in these test
6 0.2°C.
methods, refer to Terminology D1129.
6.6 Stereoscopic Microscope and Illuminator.
4. Summary of Test Methods 6.7 Illuminated Magnifying Stand for counting colonies on
agar spread plates.
4.1 Test Method A involves saturating a 47-mm absorbent
6.8 Hand Tally Counter.
pad with water and determining the volume of water held by
6.9 Autoclave.
the pad by weighing the pad dry and when fully saturated.
6.10 Analytical Balance readable to the nearest 1 mg.
4.2 TestMethodBinvolvesculturingmicro-organismsfrom
6.11 Petri Dish, 50-mm, nonsterile.
suspensions of pure cultures on a 0.45-µm membrane filter,
6.12 Expendable Equipment:
which is placed on the test absorbent pad saturated with the
6.12.1 Filters (gridded, 0.45-µm, 47-mm) sterile, for water
testing.
These methods are under the jurisdiction of ASTM Committee D19 on Water
6.12.2 Absorbent pads (47-mm), sterile for the growth test.
and are the direct responsibilities of Subcommittee D19.08 on Membranes and Ion
6.12.3 Petri dishes, sterile 50-mm and 100-mm.
Exchange Materials.
6.12.4 Pipets, sterile, 10-mL, 0.1 mL graduations, accuracy
Current edition approved Oct. 29, 1982. Published March 1983. DOI: 10.1520/
D4198-82R03.
of 65%.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.12.5 Test tubes, sterile, 20-mL, with screw caps.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.12.6 Bent glass rod, sterile, for spreading bacterial cul-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. tures.
Withdrawn. The last approved version of this historical standard is referenced
on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4198–82 (2003)
6.12.7 Burner, for flame sterilization. 11.1.4 After the pads are fully saturated (20 to 30 s), pour
off the excess water and shake out any remaining excess.
7. Reagents and Materials
11.1.5 Cover the dishes and weigh again.
7.1 Purity of Water—Unless otherwise indicated, reference
11.2 Method B—Culture Technique:
to water shall be understood to mean reagent water conforming 11.2.1 Prepare a set of ten 100-mm sterile petri dishes with
to Specification D1193, Type II, with 0.2-µm membrane
16 6 1 mL of M-FC agar. Make sure the agar plates are at
filtration. In addition, suitability tests for determining the room temperature and that the surfaces are dry before using.
bactericidal properties of the reagent grade water should be
11.2.2 Prepare a set of five 50-mm sterile petri dishes with
performed. the sterile pads. To each pad add 1.8 mL of sterile M-FC broth
7.2 M-FC Agar with Rosolic Acid—Fecal coliform medium
and pour off the excess.
specific for the membrane filter technique. 11.2.3 Test five replicate sets of three aliquots. Each repli-
7.3 M-FC Broth with Rosolic Acid—Broth nutrient for
cate shall include (a) two membrane-filtered samples (one on
bacterial growth. agar, one on a pad), and (b) one spread plate.
7.4 Peptone Water, 0.1 %.
11.2.4 Add 0.1 mL of the diluted culture solution from 10.7
7.5 E. coli (ATCC 11229). to the agar plate from 11.2.1 and using a sterile bent glass rod,
spread over the surface of
...