In addition to drug/alcohol testing required by state or federal law, an employer may require a specific employee to submit to drug/alcohol testing designed to identify the presence in the body of controlled substances referenced under chapter 69.50 RCW, other than drugs prescribed by a physician, if:

(1) The employer has a policy that:

(a) Complies with legal requirements;

(b) Establishes procedures under which the test may be conducted;

(c) Provides for the confidential treatment of drug and or alcohol test results as required by law or in an action or proceeding challenging any disciplinary action arising from the circumstances which led to the test; and

(2) One of the following conditions apply:

(a) The employee is subject to testing because:

(i) The employer has specific, objective grounds to believe the employee's work performance is impaired due to the presence of such substances in the body; or

(ii) While on duty the employee is involved in an accident or incident as described by the employer's policy;

(b) The employer determines that employees in positions with any of the following responsibilities are subject to testing:

(i) Providing security on state property or ensuring public safety;

(ii) Administering or dispensing medication; or

(iii) Utilizing a firearm as called for in performance of job duties.