49 CFR 246.120: Requirements for qualification.

(a) After FRA has approved a railroad's certification program, a railroad shall not permit or require a person to serve as a signal employee, as defined in § 246.7, unless that railroad determines that:

(1) The person is a certified signal employee; and

(2) The person either:

(i) Is qualified, as defined in § 246.7, on the signal system equipment and signal-related technology (whether existing or new) and therefore may reasonably be expected to be proficient on all safety related tasks the person is assigned to perform; or

(ii) Is working under the direct and immediate supervision of a mentor or qualified instructor.

(b) If a person is called to perform work on signal system equipment or signal-related technology that they are not qualified on, the person must immediately notify the railroad that they are not qualified on the signal system equipment or signal-related technology.

(c) A person shall no longer be considered qualified on signal system equipment or signal-related technology if they have not performed work that requires certification pursuant to this part on signal system equipment or signal-related technology in the previous 12 months.

(d) Each railroad shall adopt and comply with a program meeting the requirements of this section. When any person (including but not limited to a railroad; any manager, supervisor, official, or agent of a railroad; any owner, manufacturer, lessor, or lessee of railroad equipment, track, or facilities; any employee of such owner, manufacturer, lessor, lessee, or independent contractor or subcontractor) violates any requirement of a program which complies with the requirements of this section, that person shall be considered to have violated the requirements of this section.