Hazardous area classification design is required to reduce the explosion risk in process plants. Among the international design guidelines, only IEC 60079-10-1 proposes a new type of zone, namely zone 2 NE, to prevent explosion hazards. We studied how to meet the zone 2 NE grade for a facility handling hydrogen gas, which is considered as most dangerous among explosive gases. Zone 2 NE can be achieved considering the grade of release, as well as the availability and effectiveness of ventilation, which are factors indicative of the facility condition and its surroundings. In the present study, we demonstrate that zone 2 NE can be achieved when the degree of ventilation is high by accessing temperature, pressure, and size of leak hole. The release characteristic can be derived by substituting the process condition of the hydrogen gas facility. The equations are summarized considering relation of the operating temperature, operating pressure, and size of leak hole. Through this relationship, the non-hazardous condition can be realized from the perspective of inherent safety by the combination of each parameter before the initial design of the hydrogen gas facility.

需要危险区域分类设计来降低过程工厂的爆炸风险。在国际设计指南中，只有 IEC 60079-10-1 提出了一种新型区域，即区域 2 NE，以防止爆炸危险。我们研究了如何满足处理氢气的设施的 2 区 NE 等级，氢气被认为是爆炸性气体中最危险的。考虑到释放等级以及通风的可用性和有效性，可以实现 2 区 NE，这些因素是指示设施条件及其周围环境的因素。在本研究中，我们证明了当通风程度高时，可以通过访问温度、压力和泄漏孔的大小来实现区域 2 NE。可以通过替换氢气设备的工艺条件来导出释放特性。考虑到工作温度、工作压力和泄漏孔尺寸的关系，对方程进行了总结。通过这种关系，在氢气设施的初始设计之前，通过组合各个参数，可以从本质安全的角度实现非危险状态。