49 CFR § 231.20 - Variation in size permitted.

---
identifier: "/us/cfr/t49/s231.20"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 231.20 - Variation in size permitted."
title_number: 49
title_name: "Transportation"
section_number: "231.20"
section_name: "Variation in size permitted."
chapter_name: "FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
part_number: "231"
part_name: "RAILROAD SAFETY APPLIANCE STANDARDS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 20102-20103, 20107, 20131, 20301-20303, 21301-21302, 21304; 28 U.S.C. 2461 note; and 49 CFR 1.89."
regulatory_source: "33 FR 19663, Dec. 25, 1968, unless otherwise noted."
cfr_part: "231"
---


# 231.20 Variation in size permitted.

To provide for the usual inaccuracies of manufacturing and for wear, where sizes of metal are specified, a total variation of 5 percent below size given is permitted.