Notwithstanding the definition of "employee" in RCW 41.59.020
, the commission may exclude from the coverage of chapter 288, Laws of 1975 1st ex. sess. any specialized job category of an employer where a majority of the persons employed in that job category consists of classified employees. At such time as a majority of such employees are certificated, the job category may be considered an appropriate unit under chapter 288, Laws of 1975 1st ex. sess.