Legal analysis: The specification requirements are as follows: 1. According to the surrounding rock of the tunnel and the excavation method, the construction site should be equipped with enough pipelines and connecting materials. Besides the whole pipeline, it should also be equipped with 1m, 2m and 3m short-section pipelines and joints (135). 2. The escape pipeline must be processed before it can be used. Each unit can process according to the materials and the actual situation on site. The connection shall be simple, firm, tight and reliable, and temporary fixing measures shall be taken on the ground. During construction, the nozzle can be temporarily sealed for easy opening and closing.
Legal basis: Article 9 of the Safety Regulations for Tunnel Construction: In the early stage of tunnel construction, a safety escape pipeline should be laid in the tunnel. The starting point should be at the newly-built end of the secondary lining, and the distance from the end of the secondary lining should not be more than 5m. The pipeline shall be laid from the lining working face to an appropriate position within the range of 10 meter from the excavation face. The pipeline should be laid along the side of primary support, and working ropes should be reserved in the pipeline for escape, emergency rescue, communication and transmission after the accident.