国标的ExiaIIAT4的防爆标准，等同于日本防爆的什么等级，最好能提供日本的防爆标准

应该是e1G4。 Protection methods: d = flameproof (same concept as in IEC 60079-1, 1990) e = increased safety (same concept as in IEC 60079-7, 1990) i = intrinsic safety (same concept as in IEC 60079-11, 1991) o = oil immersion (same concept as in IEC 6007