ASTM E1766-95(2007)

Standard Test Method for Determination of Effectiveness of Sterilization Processes for Reusable Medical Devices

SCOPE
1.1 This test method covers a reproducible procedure for testing processes used to sterilize reusable medical devices (instruments). This test method is not designed to validate a sterilization process, but tests an established sterilization cycle or process. It is a practical test of the effectiveness of a sterilization process applied to reusable medical devices. Bacterial spores more resistant to the test sterilant than the natural bioburden of the instrument are used as the test organisms. Commercially available liquid suspensions of bacterial spores are used to inoculate the instruments.
1.2 This test method is intended for reusable medical devices cleaned in accordance with the device manufacturer's instructions and prepared for sterilization in accordance with the instructions for the sterilization process being used.
1.3 This test method assumes that cleaned, reusable medical devices will be free of visible soil but may have remaining adherent bioburden. A worst-case bioburden can be represented by suspensions of bacterial endospores, which are commercially available for monitoring chemical or physical sterilization processes. These endospores should have a verifiable resistance (D value) to the specific process and sterilant being evaluated.
1.4 It is impractical to test for the sterility of some devices by immersion in growth medium because of their complexity, size, and availability (for long-term incubation) or adverse effects on the devices from long-term immersion. Therefore, elution, rinsing, or swabbing techniques are used to recover test organisms from inoculated devices.
1.5 A recovery control will be included by inoculation of a test device and use of the elution methods without applying the sterilization process being tested. A minimal recovery of 106 colony-forming unit (CFU)/mL per device is required for the recovery control.
1.6 Results of the recovery control and process test cycle are compared to determine the effectiveness of the sterilization process.
1.7 Results of the recovery control and applied inoculum are compared to determine the recovery efficiency, if desired.
1.8 The procedure should reveal that tested devices are free of recoverable microorganisms when five or more consecutive tests are conducted.
1.9 A knowledge of microbiological techniques is required to conduct these procedures.
1.10 The values stated in SI units are to be regarded as the standard.
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-Oct-2007
• ICS: 11.080.10 - Sterilizing equipment
• Technical Committee: E35 - Pesticides, Antimicrobials, and Alternative Control Agents
• Drafting Committee: E35.15 - Antimicrobial Agents

Relations

• Replaces: ASTM E1766-95(2002) - Standard Test Method for Determination of Effectiveness of Sterilization Processes for Reusable Medical Devices
• Effective Date: 01-Nov-2007
• Referred By: ASTM F3127-22 - Standard Guide for Validating Cleaning Processes Used During the Manufacture of Medical Devices
• Effective Date: 01-Nov-2007

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: E1766 − 95(Reapproved 2007)
Standard Test Method for
Determination of Effectiveness of Sterilization Processes for
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Reusable Medical Devices
This standard is issued under the fixed designation E1766; 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.
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1. Scope sterilization process being tested. A minimal recovery of 10
colony-forming unit (CFU)/mL per device is required for the
1.1 This test method covers a reproducible procedure for
recovery control.
testing processes used to sterilize reusable medical devices
1.6 Resultsoftherecoverycontrolandprocesstestcycleare
(instruments). This test method is not designed to validate a
compared to determine the effectiveness of the sterilization
sterilization process, but tests an established sterilization cycle
process.
or process. It is a practical test of the effectiveness of a
sterilization process applied to reusable medical devices. Bac-
1.7 Resultsoftherecoverycontrolandappliedinoculumare
terial spores more resistant to the test sterilant than the natural
compared to determine the recovery efficiency, if desired.
bioburden of the instrument are used as the test organisms.
1.8 The procedure should reveal that tested devices are free
Commercially available liquid suspensions of bacterial spores
of recoverable microorganisms when five or more consecutive
are used to inoculate the instruments.
tests are conducted.
1.2 This test method is intended for reusable medical
1.9 A knowledge of microbiological techniques is required
devices cleaned in accordance with the device manufacturer’s
to conduct these procedures.
instructions and prepared for sterilization in accordance with
1.10 The values stated in SI units are to be regarded as the
the instructions for the sterilization process being used.
standard.
1.3 This test method assumes that cleaned, reusable medical
1.11 This standard does not purport to address all of the
devices will be free of visible soil but may have remaining
safety concerns, if any, associated with its use. It is the
adherentbioburden.Aworst-casebioburdencanberepresented
responsibility of the user of this standard to establish appro-
by suspensions of bacterial endospores, which are commer-
priate safety and health practices and determine the applica-
cially available for monitoring chemical or physical steriliza-
bility of regulatory limitations prior to use.
tion processes. These endospores should have a verifiable
resistance (D value) to the specific process and sterilant being
2. Referenced Documents
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evaluated.
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2.1 ASTM Standards:
1.4 It is impractical to test for the sterility of some devices
D1193 Specification for Reagent Water
by immersion in growth medium because of their complexity,
E1054 Test Methods for Evaluation of Inactivators of Anti-
size, and availability (for long-term incubation) or adverse
microbial Agents
effects on the devices from long-term immersion. Therefore,
elution,rinsing,orswabbingtechniquesareusedtorecovertest
3. Terminology
organisms from inoculated devices.
3.1 Definitions:
1.5 A recovery control will be included by inoculation of a
3.1.1 bioburden—the number and types of viable microor-
test device and use of the elution methods without applying the
ganisms that contaminate a device.
3.1.2 CFU—colony-forming unit.
3.1.3 inoculum—the number (usually specified as CFUs)
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This test method is under the jurisdiction of ASTM Committee E35 on
and type (genus and species) of viable microorganisms used to
Pesticides, Antimicrobials, and Alternative Control Agents and is the direct
contaminate a given sample or device.
responsibility of Subcommittee E35.15 on Antimicrobial Agents.
Current edition approved Nov. 1, 2007. Published November 2007. Originally
approved in 1995. Last previous edition approved in 2002 as E1766 – 95 (2002).
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DOI: 10.1520/E1766-95R07. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
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Oxborrow, G. S., and Berube, R., “SterilityTesting—Validation of Sterilization contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Processes, and Sporicide Testing,” Disinfection, Sterilization, and Preservation, Standards volume information, refer to the standard’s Document Summary page on
Block, S. S., 4th Edition, Lea and Febiger, Philadelphia, PA, 1991, pp. 1047–1058. the ASTM website.
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E1766 − 95 (2007)
3.1.4 sporicidal agent—any chemical or physical agent that 5. Significance
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