(a) Whils't on 'seawatch' you observe that the Oil Mist detector (OMD) in the engine room has triggered an alarm and in feeling the crankcase doors on the bottom platform, you find that the unit in question feels warmer than the rest. What pre-emptive action will you take as Watch-keeper to bring the situation under control. (10)

(b) Draw a simple line diagram of a 'OMD' and explain it's working. (6)