PDFWAC 415-104-330
What are special salary or wages?
(1) Special salary or wages for services rendered are payments that do not qualify as basic salary because the payment is based upon the attributes of the individual instead of being attached to the position. A payment is not attached to a position if it is not tied to specific duties required of all persons holding the position. Payments that are not attached to a position include but are not limited to the payments described in WAC 415-104-3302 and 415-104-3303.
(2) Longevity pay is not attached to a position because it is based upon the attributes of an individual. It is, however, specifically included as part of basic salary under RCW 41.26.030.