MEOclassIIexamnotes

Acid content inside a system can emulsify with the compressor oil to form an aggressive oil sludge that reduces lubrication properties. This can lead to serious compressor damage. Sludge can also cause a variety of other problems in a system, such as blockages of strainers, expansion valves and other tiny passage

Moisture can cause corrosion. However, moisture in combination with a HCFC refrigerant containing chlorine (like for example R-22 or R-409A) creates much more serious corrosion, as the chlorine hydrolyses with the water to form hydrochloric acid (HCl) which is aggressive to most metals. Heat adds significantly to the problem by accelerating the acid-forming process.  For HFC refrigerants (like R-404A or R-407C), it is the polyolester oils that are very hygroscopic and may decompose at high temperatures forming hydrofluoric acid with the moisture which could be introduced to the system through a sub-standard refrigerant.

There is a general average act when and only when, any extraordinary sacrifice or expenditure is intentionally and reasonably made or incurred for the common safety for preserving from peril the property involved in common maritime adventure

Certificate of Proficiency (COP) refers to a certificate, other than a certificate of competency issued to a seafarer, stating that the relevant requirements of training, competencies or seagoing service in the Convention have been met. Able seafarer deck :Person qualified in accordance with the provisions of regulation II/5 of the STCW Convention Able seafarer engine :Person qualified in accordance with the provisions of regulation III/5 of the STCW ConventionAble seafarers whether deck or engine are given Certificate of Proficiency (COP) Competency (COC) refers to the possession and demonstration/application of the knowledge, understanding and proficiency required of seafarers under the Convention. Electro - technical officer : Person qualified in accordance with the provisions of regulation III/6 of the STCW ConventionETO is given Certificate of competency (COC).

Bill of Lading (B/L) The bill of lading is the declaration of the master of the vessel by which he acknowledges that he received the goods on board of his ship and assures that he will carry the goods to the place of destination for delivery, in the same condition as he received them, against handing of the original bill of lading. "Bill of lading means a document which evidences a contract of carriage by sea and the taking over of loading of the goods by the carrier, and by which the carrier undertakes to deliver the goods against surrender of the document. A provision in the document that the goods are to be delivered to the order of a named person, or to order, or to bearer, constitutes such an undertaking." The bill of lading (B/L) serves as: A receipt of the goods by the shipowner acknowledging that the goods of the stated species, quantity and condition, are shipped to a stated destination in a certain ship, or at least received in custody of the shipowner for t...

Reversing of the engine is performed electronically and controlled by the Engine Control System,by changing the timing of the fuel injection, the exhaust valve activation and the starting valves.

Biochemical Oxygen Demand (B.O.D) Amount of oxygen taken up by sewage sample in mg/l or ppm is termed as Biochemical Oxygen Demand. Measure of strength of sewage. Identifies biological decomposable substances and is a test on the activity of bacteria, Presence of oxygen feed on and consume organic matter. Test results are expressed as amount of oxygen taken by one litre sample (diluted with aerated water)when incubated at 20°C for five days. It gauges the effectiveness of sewage treatment process. B.O.D of raw sewage is 300 to 600 mg/litre. I.M.O recommends a B.O.D of 50 mg/litre after treatment. Coliform Count Coliform organisms are recognised as the indicator Organisms of sewage pollution. Numbers present in sewage are large. Each person contributes between 125 billion, in winter to 400 billion, in summer. Coliform are present in human intestine and presence in water is taken as an indication of the pathogen count. Responsible for Typhoid, Dysentery, Polimyelitis, Cho...