Every private employer regularly employing 25 or more employees shall reasonably accommodate any employee who wishes to voluntarily enter and participate in an alcohol or drug rehabilitation program, provided that this reasonable accommodation does not impose an undue hardship on the employer.

Nothing in this chapter shall be construed to prohibit an employer from refusing to hire, or discharging an employee who, because of the employee’s current use of alcohol or drugs, is unable to perform his or her duties, or cannot perform the duties in a manner which would not endanger his or her health or safety or the health or safety of others.