The primary goal of M22-A3 is to streamline the quality control (QC) process by identifying media with high reliability that do not require exhaustive retesting by the user. Clinical & Laboratory Standards Institute | CLSI Target Audience

There is publicly available. The series appears to have been superseded by the broader CLIA regulatory changes and the introduction of the IQCP framework. The third edition remains the final and most comprehensive version of this standard.

The implementation of CLSI M22-A3 yielded profound benefits across the global healthcare landscape:

Always verify if your specific accreditation body (e.g., CAP) requires adherence to the historical M22-A3 criteria or mandates an upgrade to the latest edition.

A significant development that users must be aware of is that

For the chromatographer at the bench, the M22-A3 PDF is a technical playbook. Here are the five pillars the document emphasizes.

The standard defines an acceptable failure rate as ≤0.5% .

| Source | Details | |---|---| | | The primary source. Members can access the document at a reduced price. Non-members can purchase it directly. As an archived document, it will be less expensive than active standards. Visit clsi.org and search for "M22-A3" or "M22A3E". | | ANSI Webstore | The American National Standards Institute (ANSI) is a key partner. The PDF purchased through ANSI is the official CLSI document. Visit webstore.ansi.org . | | Accuris (formerly Techstreet) | A major standards distributor. They typically offer a "Printed Edition + PDF" package for immediate download. However, note that the CLSI no longer offers a print edition for this specific document. | | Intertek Inform | Another reputable source for purchasing standards, offering both hardcopy and PDF formats. |

Mycobacteria, nocardioform, and other actinomycetes are a group of bacteria that pose significant challenges in susceptibility testing. These organisms have complex growth requirements and are often resistant to multiple antimicrobial agents, making susceptibility testing more difficult.

CLSI M22‑A3 remains a landmark standard in the field of clinical microbiology, providing a rigorous quality‑control framework for commercially prepared culture media. While its applicability in the United States has been overtaken by the newer IQCP approach, it continues to serve as a valuable reference for international laboratories, manufacturers, and regulatory bodies.

The end-user laboratory must perform full quality control testing on every new lot number received, regardless of the manufacturer’s certificate.

Direct access to the M22 Standard and updates.