ASTM F838-05

Standard Test Method for Determining Bacterial Retention of Membrane Filters Utilized for Liquid Filtration

SCOPE
1.1 This test method determines the bacterial retention characteristics of membrane filters for liquid filtration using Pseudomonas diminuta as the challenge organism. This test may be employed to evaluate any membrane filter system used for liquid sterilization.
This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, 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: 31-Dec-2004
• Technical Committee: D19 - Water
• Drafting Committee: D19.24 - Water Microbiology

Relations

• Replaced By: ASTM F838-05(2013) - Standard Test Method for Determining Bacterial Retention of Membrane Filters Utilized for Liquid Filtration
• Effective Date: 01-Jun-2013
• Referred By: ASTM D8422-21 - Standard Practice for Pre-Stressing Terminal Point-of-Use Water Filters before Testing by Test Method F838
• Effective Date: 01-Jan-2005

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: F838 − 05
StandardTest Method for
Determining Bacterial Retention of Membrane Filters
1
Utilized for Liquid Filtration
ThisstandardisissuedunderthefixeddesignationF838;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope growth medium. Organisms that are not retained by the filter
being tested will develop into visible colonies on the analysis
1.1 This test method determines the bacterial retention
membrane and can then be enumerated.
characteristics of membrane filters for liquid filtration using
Pseudomonas diminuta as the challenge organism. This test
5. Significance and Use
maybeemployedtoevaluateanymembranefiltersystemused
5.1 Since all sterilizing filtration processes are performed
for liquid sterilization.
under positive pressure, this test method is designed to assess
1.2 This standard may involve hazardous materials,
the retentivity of a sterilizing filter under process conditions.
operations, and equipment. This standard does not purport to 7 2
5.1.1 A challenge of 10 bacteria per cm of effective
address all of the safety concerns, if any, associated with its
filtration area is orders of magnitude higher than one would
use. It is the responsibility of the user of this standard to
expecttoencounterinasterilizingfiltrationprocess.Thislevel
establish appropriate safety and health practices and deter-
wasselectedinordertoprovideahighdegreeofassurancethat
mine the applicability of regulatory limitations prior to use.
the filter would quantitatively retain large numbers of organ-
isms. This concept is important, in view of the requirement to
2. Referenced Documents
provide a quantitative assessment in validating a sterilization
2
2.1 ASTM Standards:
process.
D1193Specification for Reagent Water
5.1.2 The analytical procedure utilized in this test method
provides a method to assign a numerical value to the filtration
3. Terminology
efficiency of the filter being evaluated. This value, coupled
3.1 Definitions:
with a knowledge of the number and types of organisms
3.1.1 log reduction value—the logarithm to the base 10 of
(bioburden) indigenous to the process, may then be utilized to
the ratio of the number of microorganisms in the challenge to
determine the probability of obtaining a sterile filtrate.
the number of organisms in the filtrate.
Conversely,thenumericalvalueofthefiltrationefficiencymay
be used when one must meet a specified probability of sterility
4. Summary of Test Method
assurance to calculate the volume of fluid that may be filtered
4.1 After sterilization, the test filter is challenged with a
in order to maintain that level of assurance.
3
suspension of Pseudomonas diminuta (ATCC 19146) at a
7 2
6. Apparatus
concentration of 10 organisms per cm of effective filtration
area (EFA) at a maximum differential pressure across the test
6.1 Assemble the apparatus described below as in Fig. 1:
filterof30psig(206kPa)andaflowrateof0.5to1.0GPMper
6.1.1 Stainless Steel Pressure Vessel , 12-L capacity (or
2 -3 2
ft ofeffectivefiltrationarea(2to4×10 LPMpercm ).The
larger), fitted witha0to 50-psi (0 to 350-kPa) pressure gage.
entire filtrate is then filtered through an analytical membrane
6.1.2 Air Regulator.
filer disc which is subsequently incubated on a solidified
6.1.3 142-mm Disc Filter Assemblies , two or more, with
hose connections.
1 6.1.4 Diaphragm-Protected 0 to 50-psi Pressure Gage (0 to
This test method is under the jurisdiction ofASTM Committee D19 on Water
and is the direct responsibility of Subcommittee D19.24 on Water Microbiology.
350-kPa), for upstream pressure reading. A second equivalent
Current edition approved Jan. 1, 2005. Published February 2005. Originally
gauge for downstream pressure reading is optional.
approved in 1983. Discontinued January 2002 and reinstated in 2005 as F838–05.
6.1.5 Manifold,withvalves(autoclavable)andhoseconnec-
DOI: 10.1520/F0838-05.
2
tions.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.1.6 Autoclavable Tubing, (must be able to withstand a
Standards volume information, refer to the standard’s Document Summary page on
pressure of 50 psi (350 kPa)).
the ASTM website.
3
6.1.7 Filter Housing, with hose connections.
Available from American Type Culture Collection, 21301 Parklawn Dr.,
Brookeville, MD 20833. 6.1.8 Hose Clamps.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
F838 − 05
FIG. 1 Test Set-Up for Bacteria Retention Testing
6.1.9 Incubator, 30 6 2°C.
Trypticase
...