The Commissioner or the agent of the Commissioner shall issue a written notice to any person who operates a tower crane without a certificate of competence. The notice shall: Be in writing; Describe with particularity the nature of the alleged violation; and Include a statement signed by the employer that the employer will not allow the particular crane to operate unless there is an operator with a certificate of competence. The Commissioner's written notice or a copy of the written notice shall be posted conspicuously at or near the crane where the alleged violation occurred.