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DNV GL main class and additional considerations.

FPSO

US notation for an FPSO:

Appendix A: USCG Policy letter No. • 1-13. Normally for an FPSO (with US fag or

Ch.2: Design and equipment require- USCG acceptance of the DNV GL plan foreign fag), the following minimum • ments for meeting an equivalent level review and inspections is predicated class notations will be proposed under of safety to the USCG requirements for on the basis that such actions are in DNV GL class.

FOIs, FSOs and FPSOs operating in the accordance with the relevant class nota- 1A1 production and storage Unit

US OCS. This chapter contains com- tions and additional USCG requirements

POSMOOR ofoading pliance matrices for FOIs and FPSOs described in CG-ENG Policy Letter No. which specifes a list of supplemen- 01-13. The USCG will make decisions USCG’s and the Bureau of Safety and tal USCG requirements beyond class concerning equivalencies, or resolutions Environmental Enforcement’s (BSEE) requirements in a tabular format. The of apparent conficts in or among the main concerns for FPSOs operating in chapter also includes an informative applicable requirements. the OCS are for evacuation and seeking section on equivalencies and design shelter during a hurricane. Therefore the FPSO will require a valid tanker certifcate for evacuation during a hur- ricane situation. Therefore such FPSOs /

FSOs require a detachable/disconnect- able turret that can be relatively quickly disconnected in the event of a hurricane or extreme weather.In such situations, the vessel will adopt the tanker mode and move out to seek shelter. Therefore, the 1A1 notation (typically for mobile offshore units as opposed to permanent offshore installations) is the mandatory notation together with POSMOOR for passive mooring. Double hull require- ments in 33 CFR 157.10d(c)(1)(i) and 33

CFR 157.10d(c)(2)(i), and the require- ments in 33 CFR 157.10d(c)(3) and 33

CFR 157.11(g)(2) must be met. DNV GL- classed FPSOs complying with the rel- evant sections of the OSS document for meeting the class notation, together with the supplemental USCG requirement as documented in the compliance matrix, will be awarded the additional notation of Production and Storage Unit (US).

Supplemental USCG Requirement for

FPSO

Chapter 2 contains supplemental require- ments by the USCG that are otherwise not required under normal DNV GL class rules for the relevant FPSO notations.

These have been arranged by disci- pline in a tabular format noting the area of discipline, a description of the require- ment for clearer understanding and the item number in the policy letter for easy reference.

The main areas that have been docu- mented for USCG supplemental require- ment for FPSOs are as follows:

Stability: highlighting USCG’s require- 1. ment for intact and damage stability and MARPOL annex 1 requirement;

MODU CODE requirements; demon- stration of safe disconnection proce- dure for severe weather, etc.

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