The grades and standards established by the United States department of agriculture as of September 30, 1988, for all commodities included within the provisions of this chapter are hereby adopted as the grades and standards for such commodities in this state: PROVIDED, That the department is hereby authorized to adopt by regulation any new or future amendments to such federal grades and standards. The department is also authorized to issue regulations whether or not in accordance with the federal government and to prescribe therein grades and standards which it may deem suitable for inspection of commodities in the state of Washington. In adopting any new or amendatory regulations the department shall give appropriate consideration, among other relevant factors, to the following:
(1) The usefulness of uniform federal and state grades;
(2) The common classifications given such commodities within the industry;
(3) The utility of various grades;
(4) The kind and type of grades requested by those dealing with the particular type of commodity; and
(5) The condition of the commodity with regard to its wholesomeness and purity.