What is high-density cargo, and what are the damage stability criteria for a bulk carrier?
Short answer
| Ship | Criterion (SOLAS XII/4) |
|---|---|
| New: built on or after 1 July 1999, single-side-skin, 150 m and upwards, cargo of 1,000 kg/m³ and above | withstand flooding of any one cargo hold, loaded to the summer load line, in all loading conditions |
| Older: built before 1 July 1999, cargo of 1,780 kg/m³ and above | withstand flooding of the foremost hold, with the bulkhead and double bottom strengthened (regulation 3) |
| Satisfactory equilibrium | flooded waterline below any opening for progressive flooding; residual stability within the criteria |
- High-density cargo (SOLAS XII/1): density 1,780 kg/m³ and above (iron ore, concentrates): little volume, great weight, loaded low with high point loading.
- Damage stability: after flooding the ship still floats upright: lost buoyancy, residual GZ, no unprotected opening submerged; SOLAS II-1 attained index A at least the required R.
- XII/4, new ships (from 1 July 1999): single-side-skin bulk carriers of 150 m and upwards for cargo of 1,000 kg/m³ and above withstand flooding of any one hold, loaded to the summer load line, in all conditions.
- Older ships, cargo 1,780 kg/m³ and above: withstand flooding of the foremost hold; the bulkhead between the two foremost holds and the double bottom strong enough (regulation 3).
- Supporting: density declaration (XII/10), loading instrument (XII/11), sailing restrictions with a hold empty (XII/14), water-ingress alarms and dewatering (XII/12, 13).
- As Chief Engineer: the water-ingress alarms, bilge and ballast pumping and dewatering that buy survival time are mine.
Full answer
The full answer explains each point step by step, with the regulations and figures behind it and the discussion from other candidates. It is in the MEO Class I section of the Marine One forum, open to members enrolled for the MEO Class I exam.