沈海防爆
Gb：指定第 1 類和第 2 類裝置的防護等級。重要的是，更新後的防爆標誌進一步將防火類別分為 da、db 和 dc。
| 設備保護等級 EPL | Da | Db | Dc |
|---|---|---|---|
| 設備的防護等級是根據爆炸性氣體環境、爆炸性粉塵環境、煤礦甲烷爆炸性環境的不同特性，以及設備成為火源的可能性而規定的。 | Equipment for use in explosive dust atmospheres with a “very high” degree of protection, which is not a source of ignition under normal operation, expected failures or rare failure conditions. | Equipment for use in explosive dust environments, with a “high” degree of protection, which is not a source of ignition under normal operation or under conditions of expected failure. | Equipment for use in explosive dust environments, with a “normal” level of protection, is not a source of ignition during normal operation, and additional protective measures can be taken to ensure that effective ignition does not occur in situations where a source of ignition is expected to occur frequently (e.g. malfunctioning of a luminaire). |
| 區域 | 20 區 | 21 區 | 22 區 |
da:
專為可燃氣體偵測器中的催化感應器而設計，並獲准在 0 區使用。
db:
流行的標準，db 表示傳統的隔爆類型。
dc:
適用於電器裝置內的開關觸點和 EX 元件。