Careful consideration is required on board for proper operation of inert gas system. The oxygen content must always be maintained at 5 percent by volume; further reduction in oxygen content can lead to mixing of impurities in gas that would be hard to separate. Certain precautions must be taken prior to starting the inert gas system.
Precautions:-
1. Open all the related valves to the fuel burner; check their is adequate fuel for the operation (boiler/IGG).
2. Turn on the electric power to the control panel.
3. Water drain lines on the scrubber must be opened.
4. Ensure oxygen analyzer is working and calibrated.
5. Set the pressure control setting for the inert gas in distribution lines.
6. Set pressure control valve of the fuel burner.
6. Ensure sea water supply to deck seal.
7. Ensure the system lines are lined up.
8. Start the inert gas generator before entering the port. (Actually it is done to avoid dark black smokes coming out visible when it start).
Starting Procedure:-
1. Follow all the I.G system checklist as per the company guidelines.
2. Ensure all cargo openings are closed.
3. Line up the system prior to start.
4. Take above precautionary measures.
5. Start the Inert gas system.
6. Check for the readings of oxygen analyzer.
7. Supply inert gas to the deck opening I.G main supply valve.
8. Monitor all pressure parameters.
9. Monitor temperature and oxygen level of inert gas during the cargo operation.
10. Increase the inert gas pressure before stopping the inert gas plant.
Note: The inert gas system is only operational during the cargo discharge; any abnormality during the process lead to stop cargo operation.