PDFWAC 296-20-19020
How is it determined which impairment rating system is to be used to rate specified and unspecified disabilities?
(1) Specified disabilities are rated in one of two ways:
(a) Impairment due to amputation, total loss of hearing, and total loss of vision are rated according to RCW 51.32.080;
(b) Impairment for the loss of function of extremities, as well as partial loss of hearing or vision, is rated using a nationally recognized impairment rating guide unless otherwise precluded by department rule.
(2) Unspecified disabilities are rated in accordance with WAC 296-20-200 through 296-20-660.