How often does Hebei Construction and Lifting Company apply for a signal work permit?

Six years. The work permit issued by the building crane signalman is supervised by the housing and construction department, and the service period is 6 years, but it needs to be postponed every 2 years. Special operators have been engaged in this type of work for more than 10 years within the validity period of the special operation certificate, and strictly abide by the laws and regulations on safety in production. The review time of the special operation certificate can be extended to every 6 years 1 time with the endorsement of the original certification authority or the certification authority where the work is located. The signal company's application for employment license belongs to the special operation type, and both the Quality Supervision Bureau and the Safety Supervision Bureau can register, with the same effect.