---

A ship must have a self-contained breathing apparatus to be used as protection from gas leaking from a refrigeration unit. To meet this requirement，you may use（）.
A:a gas mask certified by the Mine Safety and Health Administration
B:the same self-contained breathing apparatus required with the fireman's outfit
C:an oxygen breathing apparatus，provided that the device has been inspected within three years
D:a portable ventilation system that will provide a complete change of air every three minutes

---

出自：海船船员证

显示答案