Haw. Rev. Stat. § 149A-34

The department may deny issuance of a certificate for reasonable cause. Any certificate issued pursuant to rules adopted under section 149A-33(1) may be suspended or revoked by the department, after hearing, for violation of any condition of the certificate or of any law or rule pertaining to the use of any restricted use pesticide. Any order made by the department for the suspension or revocation of a certificate shall be in writing and shall set forth the reasons for the suspension or revocation. The action of the department in suspending or revoking a certificate may be reviewed in the manner provided by chapter 91.