Unit type
|
Corrosion protection required and
area
|
Zone
|
Structural steelwork
|
Method
of protection required
|
Column-stabilised units
and tension-leg units
|
Submerged zone
|
Columns, lower hulls and
bracings
|
Cathodic protection and coatings,
see Notes 1 and 5
|
Boot topping and splash
zones, see Note 2
|
Columns, lower hulls and
bracings
|
Coatings
|
Atmospheric zone
|
All structure above the splash
zone
|
Coatings only
|
Self-elevating units
|
Transit condition:
Submerged, boot topping andsplash zones
|
Main hull
|
Coatings only
|
Elevated condition:
Submerged zone
|
Legs, footings and
mats
|
Cathodic protection and coatings,
see Note 5
|
Boot topping and splash
zones, see Note 4
|
Legs
|
Coatings
|
Atmospheric zone
|
All structure above the splash
zone
|
Coatings only
|
Ship units
and other surface type units
|
Submerged zone
|
Main hull
|
Cathodic protection and coatings,
see Note 1
|
Boot topping and splash
zones
|
Main hull
|
Coatings
|
Atmospheric zone
|
All structure above the splash
zone
|
Coatings only
|
Deep draught caisson units
and buoy units
|
Submerged zone
|
Main hull
|
Cathodic protection and coatings,
see Note 1
|
Boot topping and splash
zones
|
Main hull
|
Coatings
|
Atmospheric zone
|
All structure above the splash
zone
|
Coatings only
|
Mooring towers
|
Submerged zone
|
Main hull
|
Cathodic protection and coatings,
see Note 1
|
Boot topping and splash
zones, see Note 3
|
Main hull
|
Coatings
|
Atmospheric zone
|
All structure above the splash
zone
|
Coatings only
|
NOTES
|
1. For
the assignment of the In-Water Survey notation OIWS,
corrosion protection by both cathodic protection and high
resistance paint coatings is required.
|
2. For
column-stabilised units the boot topping zone is to be taken as
that part of the external structure between the maximum design
operating draught and the transit draught.
|
3. For
mooring towers the boot topping zone is to extend between the
lowest and highest atmospheric tides at the operating
location.
|
4. For
self-elevating units, in the elevated position, the boot topping
zone is to extend between the lowest and highest atmospheric
tides at the operation location.
|
5. For
mobile offshore units, if In-water Survey notation, OIWS,
is not assigned, coatings may be omitted except in the boot
topping zone, see Note 2.
|