The director of the department of labor and industries, to the extent necessary in order to prevent curtailment of opportunities for employment, shall by regulations provide for the employment of individuals whose earning capacity is impaired by physical or mental deficiency or injury, under special certificates issued by the director, at such wages lower than the prevailing rate applicable under RCW 39.12.020 and for such period as shall be fixed in such certificates.
[1972 ex.s. c 91 § 1.]