21 CFR § 660.26 - Specificity tests and avidity tests.

---
identifier: "/us/cfr/t21/s660.26"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 660.26 - Specificity tests and avidity tests."
title_number: 21
title_name: "Food and Drugs"
section_number: "660.26"
section_name: "Specificity tests and avidity tests."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "F"
subchapter_name: "BIOLOGICS"
part_number: "660"
part_name: "ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 321, 331, 351, 352, 353, 355, 360, 360c, 360d, 360h, 360i, 371, 372; 42 U.S.C. 216, 262, 263, 263a, 264."
cfr_part: "660"
---


# 660.26 Specificity tests and avidity tests.

Specificity and avidity tests shall be performed using test procedures approved by the Director, Center for Biologics Evaluation and Research.

[53 FR 12764, Apr. 19, 1988, as amended at 67 FR 9587, Mar. 4, 2002; 70 FR 14985, Mar. 24, 2005]