航海英語燃燒與爆炸單項選擇題每日一練(2019.01.10)

來源：考試資料網(wǎng)

1 Backfire flame arrestors are installed on（）.

2 A class C fire would be burning（）.

3 A cutoff valve in the fire-main system of a ship may be closed to protect the portion of the system on an exposed deck from（）.

4 The emergency signal for fires is sounded on the ship’s whistle and general alarm as（）.

5 Before using a fixed CO₂ system to fight an engine room fire，you must（）.