No person shall detonate explosives in any blasting operation unless he has passed an examination, prescribed by the Department of Labor and Industry, which shall test the examinee's skill and knowledge of the principles and practice of blasting operations and the storage, moving, handling and detonation of explosives. Application for examination as a blaster shall be in writing upon a form furnished by the department and shall be accompanied by a fee of ten dollars ($10). If the applicant is successful in passing the examination, a license indicating his competency to detonate explosives shall be issued upon the payment of an additional fee of five dollars ($5). Anything hereinbefore to the contrary notwithstanding, the department shall issue a license without examination to any applicant who shall show to the department that he has, at the effective date hereof, had three years experience in the handling and use of explosives. Each blaster shall be required to renew his license each year by application to the department, which application shall be accompanied by a fee of three dollars and fifty cents ($3.50). The Secretary of Labor and Industry may suspend any license for due cause but no license may be revoked until the licensee has been granted a hearing.