"Obey now, grieve later" - an employee should obey a supervisors lawful order and grieve the order later if the employee believes the order was in violation of a negotiated agreement or policy. There are three generally recognized exceptions to the "obey now, grieve later" rule, but the two that are most common are: 1) when the order is illegal; 2) when compliance with the order would pose a threat to the safety, health or welfare of the officer or another. This is a tricky area and extreme caution should be used before declaring an exception.
Article 17 G - When an employee believes he or she is being required to work under conditions which are unsafe or unhealthy beyond normal hazards inherent in the operation in question, he or she will refer the matter to the supervisor. The supervisor will make an evaluation of the working conditions and direct the work either be continued or stopped.
Article 17 A - The Employer agrees to provide a safe and healthful working conditions. Employees are prohibited from using vehicles not in safe operating condition.