Four don't let go: don't let go of the cause of the accident, the person responsible for the accident, the hidden danger of the accident, and all uneducated employees.

Three violations: illegal command, illegal operation and violation of labor organization discipline.

Three-level safety education refers to the factory-level safety education, workshop-level safety education and post (section, team) safety education for new employees and workers, which is the basic form of safety production education system in factories and mines. Three-level safety education system is the basic education system of enterprise safety education. Three-level safety education includes factory education, workshop education and team education. Enterprises must carry out factory education, workshop education and team education on safety production for new workers; Workers who change jobs, return to work and adopt new technologies, new processes, new equipment and new materials must be given safety and health education in new posts and new operation methods. Educated people can only be employed if they pass the exam.