Practice and procedure in and before the board are governed by the uniform procedural rules codified in the Washington Administrative Code, WAC 10-08-001 through 10-08-252, as now or hereafter amended, which rules the board adopts as its own, subject to any additional rules the board has adopted or may choose to adopt. Should any question not covered by its rules come before the board, the board reserves the right to make a determination that is fair and equitable, and in accordance with the spirit and intent of the law.