N.Y. Comp. Codes R. & Regs. tit. 16, § 262.225
(1) As soon as practicable following an accident, each operator shall test each surviving covered employee for alcohol if that employee' s performance of a covered function either contributed to the accident or cannot be completely discounted as a contributing factor to the accident. The decision not to administer a test under this section shall be based on the operator's determination, using the best available information at the time of the determination, that the covered employee's performance could not have contributed to the accident.
(3) A covered employee who is subject to post-accident testing who fails to remain readily available for such testing, including notifying the operator or operator representative of his/her location if he/she leaves the scene of the accident prior to submission to such test, may be deemed by the operator to have refused to submit to testing. Nothing in this section shall be construed to require the delay of necessary medical attention for injured people following an accident or to prohibit a covered employee from leaving the scene of an accident for the period necessary to obtain assistance in responding to the accident or to obtain necessary emergency medical care.
(b) Reasonable suspicion testing.
(3) Alcohol testing is authorized by this section only if the observations required by paragraph (2) of this subdivision are made during, just preceding, or just after the period of the work day that the employee is required to be in compliance with this Part. A covered employee may be directed by the operator to undergo reasonable suspicion testing for alcohol only while the employee is performing covered functions; just before the employee is to perform covered functions; or just after the employee has ceased performing covered functions.
(iii) Notwithstanding the absence of a reasonable suspicion alcohol test under this section an operator shall not permit a covered employee to report for duty or remain on duty requiring the performance of covered functions while the employee is under the influence of or impaired by alcohol, as shown by the behavioral, speech or performance indicators of alcohol misuse, nor shall an operator permit the covered employee to perform or continue to perform covered functions, until:
(iv) Except as provided in subparagraph (ii) of this paragraph, no operator shall take any action under this Part against a covered employee based solely on the employee's behavior and appearance in the absence of an alcohol test. This does not prohibit an operator with the authority independent of this Part from taking any action otherwise consistent with law.
(c) Return-to-duty testing.
Each operator shall ensure that before a covered employee returns to duty requiring the performance of a covered function after engaging in conduct prohibited by sections 262.215 through 262.223 of this Part, the employee shall undergo a return-to-duty alcohol test with a result indicating an alcohol concentration of less than 0.02.
(d) Follow-up testing.
(4)
(2) Follow-up testing shall be conducted when the covered employee is performing covered functions; just before the employee is to perform covered functions; or just after the employee has ceased performing such functions.
(e) Retesting of covered employees with an alcohol concentration of 0.02 or greater but less than 0.04.
Each operator shall retest a covered employee to ensure compliance with the provisions of section 262.237 of this Part, if an operator chooses to permit the employee to perform a covered function within eight hours following the administration of an alcohol test indicating an alcohol concentration of 0.02 or greater but less than 0.04.
Each operator shall conduct the following types of alcohol tests for the presence of alcohol:
(a) Post-accident.