Do nitrogen gas cylinders need safety valves?

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When searching online for instructions on how to use nitrogen cylinders, the only statement found was: “Nitrogen cylinders are equipped with pressure regulators, and these regulators have safety valves. Safety valves serve to protect the pressure regulators and ensure their safe use; they also act as a signal in case there is a malfunction with the pressure regulator.” If the outlet pressure rises on its own and exceeds a certain allowable value due to damage to the valve gasket or the valve itself, or for other reasons, the safety valve will open automatically to release air. ” The question is: What is the set pressure of the safety valve built into the pressure relief valve? It’s the “permission value” mentioned in the sentence above; it should be a fixed value ； However, the outlet pressure of the pressure regulator on a nitrogen cylinder can be adjusted according to the user’s needs; it can be set to 0.2 MPa, 0.3 MPa, 0.8 MPa, 1.0 MPa, and so on. In other words, the safety valve built into the pressure reducing valve is not intended to protect the pipes and equipment downstream of it from overpressure in the event of a failure of the pressure reducing valve. For example, assume that the set pressure of this safety valve is 0.8 MPa, and the nitrogen pressure required by the user is 0.5 MPa. In the event of a failure in the pressure reducing valve, the pressure behind the valve does not reach the activation pressure of 0.8 MPa set by the safety valve, and by then the user’s equipment and pipelines have already experienced overpressure. In that case, is it necessary to install a corresponding safety valve on the nitrogen main connected to the nitrogen cylinder, based on the design pressure of the pipes and equipment downstream?