Risk-Based Inspection Technique - Offshore Structures: Design, Construction and Maintenance - page 609

Consistency, accuracy and completeness of inspection records are important
since these data form an integral part of the structural integrity management system.
The underwater inspection programmay include one or more of the following
surveys:

General visual survey

●

Damage survey

●

Debris survey ●

Marine growth survey ●

Scour survey

●

Anode survey

●

CP surveys

●

Visual corrosion survey ●

Appurtenance inspection ●

Flooded member detection survey

●

Weld/joint close visual inspection

●

Weld/joint NDT (nondestructive testing)

●

Wall thickness. ●

8.4.4 Inspection Plan Based on ISO 9000
The inspection plan is defined after determination of the exposure level, as
shown in Table 8.32 .
It is important to highlight that the timing of the first periodic level I inspec-
tion should be determined from the date the platform installation was com-
pleted. However, the timing of the first periodic level II and level III
inspections should be determined from the date of the baseline inspection.
ISO identifies levels of survey as presented in Table 8.33 .
A level I inspection consists of a below-water verification of the performance of
the CP system (for example, a drop cell), and of an above-water visual survey. This
inspection includes a general examination of all structural members in the splash
zone and above water, concentrating on the condition of the more critical areas,
such as topside legs, girders, trusses, etc. If above-water damage is detected,

TABLE 8.32 Determination of Exposure Level

Life-safety Category Consequence Category

C1 (High
Consequence)

C2 (Medium
Consequence)

C3 (Low
Consequence)

S1 Manned non-evacuated L1 L1 L1

S2 Manned evacuated L1 L2 L2

S3 Unmanned L1 L2 L3