The conditional probability of ingress of a dangerous liquid in case of spillage from a container stowed in a vertical line not on a hatchway cover is much smaller than that in case of spillage from a container stowed on a hatchway cover. Thus, we consider that a container packed with dangerous liquids can be stowed in vertical lines not on hatchway covers regardless of the specification of the cargo hold.
3.3 Limitation of on deck stowage of a container packed with dangerous goods
Based on the above mentioned principles, it can be said that a container packed with dangerous liquids can be stowed on a hatchway cover having gaps provided that the cargo hold under the hatchway cover complies with the requirements applicable for the dangerous liquids of the relevant classes including subsidiary risks and flash points in regulation 54 in chapter II-2 of SOLAS Convention 1974, as amended (regulation 19 in new chapter II-2 of the Convention).
As described in paragraph 3.2, a container packed with dangerous liquids can be stowed in a vertical line not on a hatchway cover regardless of the specification of the cargo hold.
In conclusion, it is rational to apply the following limitation for stowage of a container on container ships with partially weatherproof hatchway covers, in addition to the stowage requirements for conventional ships with weather proof hatchway covers:
"A container packed with dangerous liquids should not be stowed on a hatchway cover having gaps, except in vertical lines at starboard and port ends on deck, unless the cargo hold under the hatchway cover complies with the requirements applicable for the dangerous liquids of the relevant classes including subsidiary risks and flash points in regulation 54 in chapter II-2 of SOLAS Convention 1974, as amended."
4 On deck only stowage
4.1 Basic principles for on deck only stowage
According to the provisions of paragraph 7.1.1.8 in PART 7 of the IMDG Code, dangerous goods which should be stowed on deck only are determined under the following principles:
(1) constant supervision is required;
(2) accessibility is particularly required; or
(3) there is a substantial risk of:
(3-1) formation of explosive gas mixtures;
(3-2) development of highly toxic vapours; or
(3-3) unobserved corrosion of the ship.
