49 CFR § 229.55 - Piston travel.

---
identifier: "/us/cfr/t49/s229.55"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 229.55 - Piston travel."
title_number: 49
title_name: "Transportation"
section_number: "229.55"
section_name: "Piston travel."
chapter_name: "FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
part_number: "229"
part_name: "RAILROAD LOCOMOTIVE SAFETY 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. 20103, 20107, 20133, 20137-38, 20143, 20168, 20701-03, 21301-02, 21304; 28 U.S.C. 2461 note; and 49 CFR 1.89."
regulatory_source: "45 FR 21109, Mar. 31, 1980, unless otherwise noted."
cfr_part: "229"
---


# 229.55 Piston travel.

(a) Brake cylinder piston travel shall be sufficient to provide brake shoe clearance when the brakes are released.

(b) When the brakes are applied on a standing locomotive, the brake cylinder piston travel may not exceed 1
1/2 inches less than the total possible piston travel. The total possible piston travel for each locomotive shall be entered on Form FRA F 6180-49A.

(c) The minimum brake cylinder pressure shall be 30 pounds per square inch.