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The CLSI M22-A3 is an essential tool for ensuring the integrity of microbiology results. While the temptation to find a free PDF is high, the risks to your laboratory’s accreditation and patient safety far outweigh the cost of a legal copy.
Before any biological testing occurs, the standard mandates visual inspection protocols for every shipment received. Laboratories must check for: Correct labeling and expiration dates.
Using pirated or unauthorized copies of proprietary standards can void a laboratory's compliance status during an audit. Inspectors look for legitimate documentation, licenses, or subscriptions. Copyright infringement can also result in steep fines for your institution. How to Access CLSI M22-A3 Legally
The CLSI M22-A3 standard, Quality Control for Commercially Prepared Microbiological Culture Media , is copyrighted material and not legally available for free download, though it provides specific guidelines for inspecting and testing media lots. A compliant report must include documentation of physical inspection, performance testing for non-exempt media, and appropriate corrective actions for any quality failures. Access the official standard at CLSI . clsi m22a3 pdf free
: You can buy the PDF version directly from the American National Standards Institute.
Assure the medium supports the growth of target organisms.
Standardized protocols for checking pH, sterility, growth performance, and selective/inhibitory properties of the media. Why Laboratories Need CLSI M22-A3 Compliance The CLSI M22-A3 is an essential tool for
This was a major philosophical shift. The "one-size-fits-all" exemptions in M22-A3 were replaced by a risk-based, site-specific assessment. Under the IQCP model, each laboratory must evaluate the risks for its specific tests, patient populations, and environment, and then design a quality control plan to mitigate those risks.
Upon arrival, logs are generated to verify the physical integrity of the shipment. Staff inspect for: Exceeded expiration dates. Signs of freezing or overheating during transit. Hemolysis in blood-containing agars. Uneven depth, bubbles, or cracked agar surfaces. Visible bacterial or fungal contamination. Step 2: Documentation Review
The manufacturer must ensure the media meets specific performance standards. Laboratories must check for: Correct labeling and expiration
: CLSI is a non-profit organization that funds its standard-development through the sale of these documents. Authorized copies are typically purchased directly from the CLSI Shop .
The M22-A3 standard covers the following topics:
While they may be exempt from testing every batch, users are responsible for inspecting media upon arrival, checking for sterility, verifying growth promotion for selective media, and documenting the receipt and inspection. "Exempt" Media in M22-A3
CLSI M22A3 is a guideline document that outlines the standard methods for antimicrobial susceptibility testing of bacteria isolated from clinical specimens. The document provides detailed procedures for testing the susceptibility of bacteria to various antimicrobial agents, including antibiotics, antifungals, and antivirals. The guidelines are designed to help clinical laboratories perform accurate and reliable susceptibility testing, which is critical for guiding patient care and controlling the spread of infectious diseases.