(1) violated any provision of, or any obligation imposed by this chapter or has violated any law in the course of any activities for which such certificate is required;
(2) made a material misstatement in the application for such certificate;
(3) been guilty of fraudulent or dishonest practices; or
(4) demonstrated his incompetency or untrustworthiness.
(b) Before revoking or suspending any such certificate, the superintendent shall give to the person and the employer of the person named in such certificate notice of hearing as specified in this chapter.