(a) Purpose. The purpose of random alcohol and drug testing is to promote safety by deterring regulated employees from misusing drugs and abusing alcohol.

(b) Regulated employees. Each railroad must ensure that a regulated employee is subject to being selected for random testing as required by this subpart whenever the employee performs regulated service on the railroad's behalf.

(c) Contractor employees and volunteers. A regulated employee who is a volunteer or an employee of a contractor to a railroad may be incorporated into the random testing program of more than one railroad if:

(1) The contractor employee or volunteer is not already part of a random testing program that meets the requirements of this subpart and has been accepted by the railroad for which he or she performs regulated service (as described in § 219.609); or

(2) The railroad for which the contractor employee or volunteer performs regulated service is unable to verify that the individual is part of a random testing program acceptable to the railroad that meets the requirements of this subpart.

(d) Multiple DOT agencies. (1) If a regulated employee performs functions subject to the random testing requirements of more than one DOT agency, a railroad must ensure that the employee is subject to selection for random drug and alcohol testing at or above the current minimum annual testing rate set by the DOT agency that regulates more than 50 percent of the employee's DOT-regulated functions.

(2) A railroad may not include a regulated employee in more than one DOT random testing pool for regulated service performed on its behalf, even if the regulated employee is subject to the random testing requirements of more than one DOT agency.