(a) Labels or bulk certificates will be issued by the department, only to the applicant or his agent. No mutilation of labels or bulk certificates, by writing or marking over, or otherwise altering original information printed thereon, will be permitted. The responsibility of proper use of labels and bulk certificates is placed on the person to whom such articles have been issued.(b) A seal shall be placed on the conveyance doors of bulk shipment containers identified by a bulk certificate.