2.1.1 Ships subject to the
Code should survive the normal effects of flooding following assumed
hull damage caused by some external force. In addition, to safeguard
the ship and the environment, the cargo tanks should be protected
from penetration in the case of minor damage to the ship resulting,
for example, from contact with a jetty or tug, and given a measure
of protection from damage in the case of collision or stranding, by
locating them at specified minimum distances inboard from the ship's
shell plating. Both the damage to be assumed and the proximity of
the tanks to the ship's shell should be dependent upon the degree
of hazard presented by the product to be carried.
2.1.2 Ships subject to the
Code should be designed to one of the following standards:
-
.1
A type 1G ship
is a gas carrier intended to transport products indicated in chapter
19 which require maximum preventive measures to preclude the escape of
such cargo.
-
.2
A type 2G ship
is a gas carrier intended to transport products indicated in chapter
19 which require significant preventive measures to preclude the escape
of such cargo.
-
.3
A type 2PG ship
is a gas carrier of 150m in length or less intended to transport products
indicated in chapter 19 which require significant preventive measures to
preclude escape of such cargo, and where the products are carried in independent
type C tanks designed (see 4.2.4.4) for a MARVS of at least 7 bar gauge and a cargo
containment system design temperature of -55°C or above. Note that a ship of this
description but over 150m in length is to be considered a type 2G ship.
-
.4
A type 3G ship
is a gas carrier intended to carry products indicated in chapter
19 which require moderate preventive measures to preclude the escape of
such cargo.
Thus a type 1G ship is a gas carrier intended for the transportation
of products considered to present the greatest overall hazard and
types 2G/2PG and type 3G for products of progressively lesser hazards.
Accordingly, a type 1G ship should survive the most severe standard
of damage and its cargo tanks should be located at the maximum prescribed
distance inboard from the shell plating.
2.1.3 The ship type required
for individual products is indicated in column c in the table of chapter
19.
2.1.4 If a ship is intended
to carry more than one product listed in chapter
19, the standard of damage should correspond to that product
having the most stringent ship type requirement. The requirements
for the location of individual cargo tanks, however, are those for
ship types related to the respective products intended to be carried.