ISO 19905-3 pdf download – Petroleum and natural gas industries — Site-specific assessment of mobile offshore units — Part 3: Floating units

ISO 19905-3 pdf download – Petroleum and natural gas industries — Site-specific assessment of mobile offshore units — Part 3: Floating units.
ISo 13624-I, Petroleum and natural gas industries — Drilling and production equipment — Part 1: Design and operation of marine drilling riser equipment
ISO 19900, Petroleum and natural gas industries — General requirements for ofishore structures
ISO) 19901-1. Petroleum and natural gas Industries — Specific requirements for offshore structures — Port 1: Metocecm design and operating considerations
ISO 19901-7. Petroleum and natural gas industries — Specific requirements for offshore structures — Part 7: Srauonkeeping systems for floating offshore structures and mobile offshore units
ISO 19904-1, Petroleum and natural gas industries — Floating offshore structures — Part 1: Ship-shaped,
semi-submersible, spar and shallow-draught cylindrical structures
ISO 19906:2019, Petroleum and natural gas industries — Arctic offshore structures
ISO 35104. Petroleum and natural gas industries — Arctic operations — Ice management International Marine Contractors Association, ‘Guidance on Operational Activity Planning. IMCA M 220
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 19900, ISO 19901-1. ISO 19901-7. ISO 19904-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardizatLon at the following addresses:
— ISO Online browsing platform: available at https:JJwwwiso.orJobp
— IEC Electropedia: available at http:J/www.electropedia.org/
3.1
activity specific operating guidelines
ASOG
document that sets out the activities that need to be undertaken at specific alert level thresholds (3,4) for specified changes in conditions
Note I to entry: These guidelines are In a document that sets out high level actions to be undertaken at specific alert level thresholds.
Note 2 to entry: The ASOG for drilling operations is often called the well specific operating guideline document (WSOG).
Note 3 to entry: An example ASOG for DP (dynamic positioning) and moorrd units Is given In Annex A.
3.2
air gap
distance between the highest water elevation and the lowest exposed part of the primary deck structure and permanent equipment not designed to withstand associated environmental action effects
[SOURCE: ISO 19900:2019. 3.5. modified — ‘structure’ and ‘action effects’ not defined herein. ‘and permanent equipment’ added and “For defined return period’ deleted.]
Mobile floating units that do not conform with this requirement shall be assessed in accordance with the provisions of ISO 19904-1, supplemented by methodologies from this document, where applicable.
5.2 Assessment
The objective of the assessment is to show that the acceptance criteria are met. Annex B provides a diagrammatic example ni the process to be used in the site-specific assessment of a mobile floating unit. Other approaches may be applied: they shall be shown to give a level of reliability equivalent, or superior, to that implicit in this document.
In situations where hydrocarbons are being produced, the requirements of this document should be supplemented by those necessary to account for any additional risk.
5.3 Exposure levels
The exposure level for each site-specific assessment of a mobile floating unit shall be
a) determined by the unit owner and the operator,
b) where applicable, agreed by the regulator and the operator, and
c) where applicable, agreed by the regulator and operator(s) of adjacent facilities.
NOTE Adjacent facilities (workover platform, local platforms, transport lines, subsea facilities, etc.) are those that are sufficiently close to the unit for there to be a potential for Impact if the unit drifts from location. Exposure levels are defined in ISO 19900, with the following additional criteria:
— L1: The extreme storm event used in assessment of the hull, referenced in Clause B. shall be the 50 year independent extremes or the classed return period, where it is known and more onerous.
— L2: The extreme storm event used in assessment of the hull, referenced in C1ause for exposure level 12 shall be the 50 year independent extremes that could be reached at the site prior to evacuation being effected (e.g. 50 year 48 hour notice sudden hurricane in tropical revolving storm areas). The unmanned post evacuation case shall be considered according to criteria to be agreed between the operator and the unit owner.