15.1.1 No cargo tanks should
have a higher filling limit (FL) than 98% at the reference temperature,
except as permitted by 15.1.3.
15.1.2 The maximum loading
limit (LL) to which a cargo tank may be loaded should be determined
by the following formula:
where:
|
LL |
= |
loading limit
expressed in percent which means the maximum allowable liquid volume
relative to the tank volume to which the tank may be loaded; |
|
FL |
= |
filling limits
as specified in 15.1.1 or 15.1.3;
|
|
ρR |
= |
relative
density of cargo at the reference temperature; and |
|
ρL |
= |
relative
density of cargo at the loading temperature. |
15.1.3 The Administration
may allow a higher filling limit (FL) than the limit of 98% specified
in 15.1.1 at the reference temperature,
taking into account the shape of the tank, arrangements of pressure
relief valves, accuracy of level and temperature gauging and the difference
between the loading temperature and the temperature corresponding
to the vapour pressure of the cargo at the set pressure of the pressure
relief valves, provided the conditions specified in 8.2.17 are maintained.
15.1.4 For the purpose of
this chapter only, “reference temperature” means:
-
.1 the temperature corresponding to the vapour
pressure of the cargo at the set pressure of the pressure relief valves when no
cargo vapour pressure/temperature control as referred to in chapter
7 is provided;
-
.2 the temperature of the cargo upon termination of
loading, during transport, or at unloading, whichever is the greatest, when a
cargo vapour pressure/temperature control as referred to in chapter
7 is provided. If this reference temperature would result in the cargo
tank becoming liquid full before the cargo reaches a temperature corresponding to
the vapour pressure of the cargo at the set pressure of the relief valves required
in 8.2,
an additional pressure relieving system complying with 8.3 should
be fitted.
15.1.5 The Administration
may allow type C tanks to be loaded according to the following formula
provided that the tank vent system has been approved accordance with 8.2.18:
where:
|
LL |
= |
loading limit
as specified in 15.1.2;
|
|
FL |
= |
filling limits
as specified in 15.1.1 or 15.1.3;
|
|
ρR |
= |
relative
density of cargo at the highest temperature which the cargo may reach
upon termination of loading, during transport, or at unloading, under
the ambient design temperature conditions described in 7.1.2; and
|
|
ρL |
= |
as specified
in 15.1.2.
|
This paragraph does not apply to products requiring a type 1G
ship.