49 CFR 240.205: Procedures for determining eligibility based on prior safety conduct.

(a) Each railroad, prior to initially certifying or recertifying any person as an engineer for any class of service other than student, shall determine that the person meets the eligibility requirements of § 240.115 involving prior conduct as a motor vehicle operator, § 240.117 involving prior conduct as a railroad worker, and § 240.119 involving substance abuse disorders and alcohol/drug rules compliance.

(b) In order to make the determination required under paragraph (a) of this section, a railroad shall have on file documents pertinent to the determinations referred to in paragraph (a) of this section, including a written document from its DAC either reflecting his or her professional opinion that the person has been evaluated as not currently affected by a substance abuse disorder or that the person has been evaluated as affected by an active substance abuse disorder and is ineligible for certification.