The deterministic method is used in particular cases where the strict application of EN 62305-2, IEC 62305-2 and NF C 17-102 standards is not suitable.
The example of the storage tanks of dangerous materials (polluting, inflammable or explosive) is the most obvious.
Since the R1 risk is about human life loss, people are at low risk for being absent in and around these tanks.
In this case, it is difficult to consider the risk of fire or pollution as eligible. Therefore we can mandate a level of protection for some structures.
NF EN 62305-2 standard states in Annex E that in the case of a structure with a risk of explosion, the minimum level of protection to set up is level II. This is one of the possible ways for this deterministic method.