防爆電氣設備用金屬材料規範

防爆電氣設備中的金屬材料需​​要考慮的一個關鍵方面是它們透過機械火花點燃爆炸性氣體-空氣混合物的傾向. 研究表明，這些金屬的成分對其著火潛力起著重要作用. To prevent the occurrence of mechanical spark ignition in metal enclosures, specific elemental limitations are mandated. The standards for 霹靂 環境 – General Equipment Requirements – specify the following:

Ⅰ類

In producing RPL level MA or Mb 防爆電氣設備, the composition of aluminum, 鎂, titanium, and zirconium in the enclosure materials must not exceed 15% by mass, and the combined mass percentage of titanium, 鎂, and zirconium must not surpass 7.5%.

二級

For Class II explosion-proof electrical equipment production, the total mass percentage of critical elements in enclosure materials varies based on the protection level: For EPLGa equipment, the total content of aluminum, 鎂, titanium, and zirconium must not exceed 10%, with magnesium, titanium, and zirconium not exceeding 7.5% in total; For EPLGb equipment, the aggregate content of magnesium and titanium must not exceed 7.5%; In the case of EPLGc equipment, apart from fans, fan covers, and ventilation hole baffles meeting EPLGb standards, there are no additional specific requirements.

三級

In manufacturing Class III explosion-proof electrical devices, the required total mass percentage of pertinent elements in the enclosure materials also varies with the protection level: For EPLDa devices, magnesium and titanium content should not exceed 7.5%; For EPLDb devices, the same limitation applies; For EPLDc devices, apart from fans, fan covers, and ventilation hole baffles adhering to EPLDb criteria, there are no further special requirements.