If separating effect is not good, which measure should be taken （）

The additional mark （）in the Classification Certificate for Machinery means propulsion apparatus is remotely controlled on the navigating bridge control station, and engine assembly control station is unmanned periodically.

A purge recovery system is used in a centrifugal air conditioning or refrigeration system to （）

The Port State Control officer may witness a fire drill carried out by the crew assigned to these duties on the（）

One of the reasons that cause oil flowed from sludge outlet of a self-cleaning separator is（）

If two A.C.generators are to be operated in parallel, the load is distributed evenly by（）

Flame failure in an automatically fired auxiliary boiler can from a/an （）

Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）

（）are used to digest the sewage to produce innocuous sludge in a biological sewage treatment plant.

The main purpose of port State control is not to（）