How to determine the number of safety designs for boilers

Is it the number of boiler safety valves? According to the Regulations on the Inspection of Boilers in the Power Industry, each boiler must be equipped with at least two safety valves. Safety valves must be installed on the boiler drum, superheater outlet, reheater inlet and outlet, as well as on the start-up separator of once-through boilers. For boilers at medium pressure and above, there are also working safety valves and control safety valves for the same vessel (such as the drum or superheater outlet header). For boilers equipped with superheaters, the steam discharge capacity of the safety valves is specified as follows: the total discharge capacity of the drum safety valves must be greater than 75% of the total evaporation rate of the drum, and the sum of the steam discharge capacities of all safety valves on both the drum and the superheater must be greater than the boiler’s maximum continuous evaporation rate. Once all safety valves have opened, the increase in boiler steam pressure shall not exceed 3% of the setting pressure of the service safety valve, nor shall it cause the pressure in any part of the boiler to exceed 8% of the calculated service pressure. The total steam discharge from the reheat apparatus’ s inlet and outlet safety valves is 100% of the reheater’s maximum design flow rate. The steam discharge rate of the safety valve on the startup separator of a DC boiler should be greater than the steam generation rate during boiler startup.