Each conveyance for persons generally engaging in winter sports recreational activities, as described in RCW 79A.40.010, shall have a current seasonal certificate to operate on a form approved and provided by the commission. Said certificate covers either winter or summer. Additional inspections may be made as deemed necessary by the director. No conveyance shall be operated for use by the public unless a valid current certificate has been issued by the director. The certificate shall be:

(1) Signed by the director.

(2) Posted in a conspicuous location at the main loading terminal during periods of operation for public use.

(3) Adequately protected from the elements.