Blasting technician, safety officer, blaster and three-member certificate are all unified examinations organized by the local public security bureau once a year, and now they have to study once a year. It is a list of people that my unit reported to the Public Security Bureau to take the exam. It is a collective declaration of the company, and individuals cannot register. The examination time is irregular in September-1 1, depending on the arrangement of the public security bureau. After graduation, just find a unit and take the exam again. It's no use taking an exam at school. The blasting certificate shall be reviewed once a year. A person can only hold one of the three certificates, and a blaster can't be a security officer.