42 CFR § 493.929 - Chemistry.

---
identifier: "/us/cfr/t42/s493.929"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "42 CFR § 493.929 - Chemistry."
title_number: 42
title_name: "Public Health"
section_number: "493.929"
section_name: "Chemistry."
chapter_name: "CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "G"
subchapter_name: "STANDARDS AND CERTIFICATION"
part_number: "493"
part_name: "LABORATORY REQUIREMENTS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 263a, 1302, 1395x(e), 1395x(s)(3) and (s)(17)."
regulatory_source: "55 FR 9576, Mar. 14, 1990, unless otherwise noted."
cfr_part: "493"
---


# 493.929 Chemistry.

The subspecialties under the specialty of chemistry for which a proficiency testing program may offer proficiency testing are routine chemistry, endocrinology, and toxicology. Specific criteria for these subspecialties are listed in §§ 493.931 through 493.939.