(a) All poles, posts, piling, timber, laminated timber, lumber, or other timber products treated with creosote and oil-borne preservatives, as provided for in this part, shall be branded or marked clearly and with reasonable permanency before being sold or offered for sale in this state, provided that lumber of less than two inches actual in thickness shall have not less than 20 percent of the pieces in each shipment branded or marked.

(b) All lumber and plywood treated with waterborne preservatives shall comply with the American Wood Preservers' Bureau standards.

(c) Every brand shall be registered with the Commissioner and shall not be identical to nor closely resemble that of any other company as listed in "Currently Used Brands" (M6-72) in the current manual of the American Wood Preservers' Association or as the listings may be updated from time to time.