49 CFR § 218.23 - Blue signal display.

---
identifier: "/us/cfr/t49/s218.23"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 218.23 - Blue signal display."
title_number: 49
title_name: "Transportation"
section_number: "218.23"
section_name: "Blue signal display."
chapter_name: "FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
part_number: "218"
part_name: "RAILROAD OPERATING PRACTICES"
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, 20131, 20138, 20144, 20168; 28 U.S.C. 2461 note; and 49 CFR 1.89."
regulatory_source: "44 FR 2175, Jan. 10, 1979, unless otherwise noted."
cfr_part: "218"
---


# 218.23 Blue signal display.

(a) Blue signals displayed in accordance with § 218.25, 218.27, or 218.29 signify that workers are on, under, or between rolling equipment. When so displayed—

(1) The equipment may not be coupled to;

(2) The equipment may not be moved, except as provided for in § 218.29;

(3) Other rolling equipment may not be placed on the same track so as to reduce or block the view of a blue signal, except as provided for in § 218.29 (a), (b) and (c); and

(4) Rolling equipment may not pass a displayed blue signal.

(b) Blue signals must be displayed in accordance with § 218.25, 218.27, or 218.29 by each craft or group of workers prior to their going on, under, or between rolling equipment and may only be removed by the same craft or group that displayed them.