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Technical requirements for high-hazard media: Mandatory requirements for pressure vessels containing extremely or highly hazardous media (Group 1) are as follows: 01 The test pressure for graphite-made pressure vessels must not be less than 1.75 times the design pressure. 02 Graphite pressure vessels shall undergo leakage tests on all joints and connections at a test pressure not lower than the design pressure; the testing method shall be specified by the designer. 03 For graphite pressure vessels, the designer shall specify in the design documents the requirements for preparing adhesive specimens, and define the number of specimens, the methods of preparation, the inspection and testing procedures, the acceptance criteria, and the requirements for retesting in case of non-conformity. 04 Fiber-reinforced plastic containers must not be used. 05 The process qualification report (CMQ) for graphite pressure vessels shall include the permeability coefficient. 06 When it is necessary to enter the container for regular inspections, replacement, neutralization, disinfection, cleaning, and sampling for analysis must be carried out. The results of these analyses must meet the relevant standards and specifications, and the interval between sampling analyses should comply with the regulations set by the user entity. 07 During regular inspections, if the material is unknown, its identity must be determined. 08 During regular inspections, a leak test shall be conducted in accordance with the requirements of the design drawings. 09 A conduit should be installed at the outlet of the safety valve or rupture disc to direct the discharged medium to a safe location where it can be properly handled; toxic materials must not be released directly into the atmosphere. 10 To facilitate the cleaning and replacement of safety valves, a stop valve may be installed between the overpressure relief device and the pressure vessel only with the approval of the person in charge of safety management at the user facility, and provided that reliable preventive measures are put in place; the structure and diameter of the stop valve must not prevent the safe operation of the overpressure relief device.