Canada Oil and Gas Installations Regulations (SOR/96-118)

Design of Offshore Platforms

39 Every offshore platform shall be designed in accordance with

• (a) for composite ice-resisting walls, section 13 of Canadian Standards Association CAN/CSA-S473-92, Steel Structures, Offshore Structures;

• (b) for the foundation, section 5 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures;

• (c) for a steel platform, sections 9, 10, 11, 12 and 16 of Canadian Standards Association CAN/CSA-S473-92, Steel Structures, Offshore Structures;

• (d) for a concrete platform, sections 8, 9, 10 and 12 of Canadian Standards Association Preliminary Standard S474-M1989, Concrete Structures; and

• (e) for a gravity base, fill, fill-retention or piled platform, section 6, 7, 8 or 9 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures, as applicable.

Design of Onshore Installations

40 Onshore installations shall be designed in accordance with the National Building Code of Canada and the National Fire Code, issued by the National Research Council of Canada.

Offshore Analyses

• 41 (1) Analyses undertaken in respect of an offshore installation for the purposes of subsection 37(2) shall cover all relevant structural elements of the offshore installation, shall be based on good engineering practice and shall include a

  • (a) structural analysis;

  • (b) fatigue analysis;

  • (c) structural element stability analysis;

  • (d) overall installation stability analysis;

  • (e) for a mobile offshore platform, intact and damage stability analysis; and

  • (f) hydrodynamic analysis.

• (2) Analyses undertaken in respect of an offshore platform for the purposes of subsection 37(2) shall be carried out in accordance with

  • (a) section 4.6.7 of Canadian Standards Association CAN/CSA-S471-92, General Requirements, Design Criteria, the Environment, and Loads;

  • (b) for a steel platform, section 8 of Canadian Standards Association CAN/CSA-S473-92, Steel Structures, Offshore Structures; and

  • (c) for a concrete platform, sections 8 and 9 of Canadian Standards Association Preliminary Standard S474-M1989, Concrete Structures.

• (3) A fatigue analysis undertaken in respect of an offshore platform for the purpose of subsection 37(2) shall be carried out in accordance with

  • (a) for a steel platform, section 14 of Canadian Standards Association CAN/CSA-S473-92, Steel Structures, Offshore Structures; and

  • (b) for a concrete platform, section 8.5 of Canadian Standards Association Preliminary Standard S474-M1989, Concrete Structures.

• (4) The foundation of major machinery and equipment on an offshore installation shall be analysed to determine if the resulting deflection, stresses and vibration are within the limits of the structural design criteria for the equipment.

Innovations for Offshore Installations

42 The design of an offshore installation shall not involve the use of any design method, material, joining technique, or construction technique that has not previously been used in comparable situations, unless

• (a) there have been engineering studies or prototype or model tests that demonstrate the adequacy of the method, material or technique; and

• (b) the operator implements a performance monitoring and inspection program that is designed to permit the determination of the correctness of the method, material or technique.

Removal and Abandonment of Fixed Offshore Production Installations

43 Where the removal of a fixed offshore production installation is a condition of a development plan approval, the operator shall incorporate in the design of the installation such measures as are necessary to facilitate its removal from the site without causing a significant effect on navigation or the marine environment.

Concept Safety Analysis for Offshore Production Installations

• 44 (1) Every operator shall, at the time the operator applies for a development plan approval in respect of an offshore production installation, submit to the Chief a concept safety analysis of the offshore production installation in accordance with subsection (5), that considers all components and all activities associated with each phase in the life of the production installation, including the construction, installation, operation and removal phases.

• (2) The concept safety analysis referred to in subsection (1) shall

  • (a) be planned and conducted in such a manner that the results form part of the basis for decisions that affect the level of safety for all activities associated with each phase in the life of the production installation; and

  • (b) take into consideration the quality assurance program selected in accordance with section 4.

• (3) Target levels of safety for the risk to life and the risk of damage to the environment associated with all activities within each phase of the life of the production installation shall be defined and shall be submitted to the Chief at the time the operator applies for a development plan approval.

• (4) The target levels of safety referred to in subsection (3) shall be based on assessments that are

  • (a) quantitative, where it can be demonstrated that input data are available in the quantity and of the quality necessary to demonstrate the reliability of the results; and

  • (b) qualitative, where quantitative assessment methods are inappropriate or not suitable.

• (5) The concept safety analysis referred to in subsection (1) shall include

  • (a) for each potential accident, a determination of the probability or susceptibility of its occurrence and its potential consequences without taking into account the plans and measures described in paragraphs (b) to (d);

  • (b) for each potential accident, contingency plans designed to avoid the occurrence of, mitigate or withstand the accident;

  • (c) for each potential accident, personnel safety measures designed to

    • (i) protect, from risk to life, all personnel outside the immediate vicinity of the accident site,

    • (ii) provide for the safe and organized evacuation of all personnel from the production installation, where the accident could lead to an uncontrollable situation,

    • (iii) provide for a safe location for personnel until evacuation procedures can be implemented, where the accident could lead to an uncontrollable situation, and

    • (iv) ensure that the control station, communications facilities or alarm facilities directly involved in the response to the accident remain operational throughout the time that personnel are at risk;

  • (d) for each potential accident, appropriate measures designed to minimize the risk of damage to the environment;

  • (e) for each potential accident, an assessment of the determination referred to in paragraph (a) and of the implementation of the plans and measures described in paragraphs (b) to (d);

  • (f) a determination of the effects of any potential additional risks resulting from the implementation of the plans and measures described in paragraphs (b) to (d); and

  • (g) a definition of the situations and conditions and of the changes in operating procedures and practices that would necessitate an update of the concept safety analysis.

• (6) The determinations and assessments required by paragraphs (5)(a) and (e), respectively, shall be

  • (a) quantitative, where it can be demonstrated that input data is available in the quantity and of the quality necessary to demonstrate reliability of the results; and

  • (b) qualitative, where quantitative assessment methods are inappropriate or not suitable.

• (7) The plans and measures identified in paragraphs (5)(b) to (d) shall be designed to ensure that the target levels of safety as defined pursuant to subsection (3) are met.

• (8) The operator shall maintain and update the concept safety analysis referred to in subsection (1) in accordance with the definition of situations, conditions and changes referred to in paragraph (5)(g) to reflect operational experience, changes in activity or advances in technology.

Offshore Environmental Criteria and Loads

• 45 (1) For the purposes of undertaking the analyses referred to in section 41, the determination of environmental criteria and loads on an offshore installation shall be made in accordance with sections 5 and 6.5 to 6.13 of Canadian Standards Association CAN/CSA-S471-92, General Requirements, Design Criteria, the Environment, and Loads.

• (2) For the purposes of undertaking the analyses referred to in section 41, permanent loads, operational loads and accidental loads shall be determined in accordance with sections 6.2, 6.3 and 6.4, respectively, of Canadian Standards Association CAN/CSA-S471-92, General Requirements, Design Criteria, the Environment, and Loads.

• (3) For the purposes of undertaking the analyses referred to in section 41, for offshore installations, load combinations shall be determined in accordance with section 6.14 of Canadian Standards Association CAN/CSA-S471-92, General Requirements, Design Criteria, the Environment, and Loads.

Offshore Site Investigations

• 46 (1) Offshore site investigations shall be carried out, for the purpose of undertaking the analyses referred to in section 41, in accordance with section 4 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures.

• (2) Where permafrost is present at a production site, the geotechnical investigation for the purposes of undertaking the analyses referred to in section 41 shall include sampling of the permafrost.

• (3) The analysis of all fill sources for an offshore installation shall meet the requirements of section 7.3.2 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures, and shall include sampled boreholes and laboratory testing of the recovered samples.

Geotechnical Parameters for the Offshore

47 For the purposes of undertaking the analyses referred to in section 41, the geotechnical parameters used for stability, deformational and thermal analyses shall be selected in accordance with section 5.2.5 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures.

Soil Deformation Offshore

48 For the purposes of undertaking the analyses referred to in section 41, the analysis for determining the deformation of foundations offshore shall be made in accordance with sections 5.2.4, 6.1.3, 7.1.3, 8.1.3 and 9.2.4 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures.

Erosion Offshore

• 49 (1) For the purposes of undertaking the analyses referred to in section 41, the analysis of the erosion offshore shall be made in accordance with sections 6.2.3, 7.2.2 and 9.3.5 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures.

• (2) Where there is a potential for erosion around an offshore platform to a degree that would affect the stability of the platform, the platform shall be

  • (a) provided with means of erosion protection that eliminate or prevent that degree of erosion; or

  • (b) designed assuming all materials that are not resistant to erosion, determined from physical or numerical modelling, are removed.

• (3) The operator of an offshore platform or drilling unit that is placed so close to an existing offshore platform as to cause erosion that affects the stability of the existing platform shall take measures to prevent that erosion.

Materials for Offshore Installations

• 50 (1) Notwithstanding compliance with the standards referred to in this Part, all materials used in an offshore installation shall be suitable for the service in which, and for the conditions under which, they are used.

• (2) No materials other than non-combustible materials shall be used in an offshore installation except where a special property is required that cannot be obtained by using a non-combustible material.

• (3) Subject to subsection (4), materials, such as organic foam insulation, that may give off toxic fumes or smoke when ignited shall not be used in an offshore installation.

• (4) Combustible foam insulation may be used for cold storage or refrigerated spaces on an offshore installation if

  • (a) the foam is of a fire retardant type;

  • (b) the foam is totally enclosed in stainless steel or another corrosion-resistant material that has all joints sealed; and

  • (c) the insulation and its casing does not form any part of the accommodation deck or bulkhead.

• (5) All structural concrete used in an offshore installation shall be in accordance with sections 4, 5 and 6 of Canadian Standards Association Preliminary Standard S474-M1989, Concrete Structures.

• (6) All structural steel used in an offshore installation shall be in accordance with sections 5, 6 and 17 of Canadian Standards Association CAN/CSA-S473-92, Steel Structures, Offshore Structures.

Air Gap and Freeboard

• 51 (1) Subject to subsection (2), the air gap for an offshore installation, except for a surface platform, shall be determined in accordance with section 4.8 of Canadian Standards Association CAN/CSA-S471-92, General Requirements, Design Criteria, the Environment, and Loads.

• (2) The air gap for a column-stabilized mobile offshore platform may be calculated assuming the platform is at survival draft and at its lowest position relative to sea level, as determined from its motion characteristics.

• (3) Every surface mobile offshore platform shall have sufficient freeboard, taking into consideration the environmental criteria and loads at the drill or production site determined under section 45.

• (4) Every fixed offshore production platform shall have sufficient freeboard to prevent ice rubble or waves from flowing over the side of the platform unless it is designed to withstand the loads due to water and ice without major damage, under the most severe conditions as determined pursuant to section 45.

Offshore Load Measuring System

52 Each leg on every self-elevating mobile offshore platform shall have a load measuring system that will permit

• (a) registration of the load on the leg at any time during jacking operations; and

• (b) measurement of the load on the leg periodically.

Gravity-Base, Fill, Fill-Retention and Self-elevating Platforms in the Offshore

53 Every gravity-base, fill, fill-retention and self-elevating platform shall be designed in accordance with sections 5, 6, 7 and 8, respectively, of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures, and section 5.2.2 of Canadian Standards Association Special Publication S472.1-1992, Commentary to CSA Standard CAN/CSA-S472-92, Foundations.

Pile Foundations

54 Pile foundations of every fixed offshore platform and, where applicable, subsea production system shall be designed in accordance with section 9 of Canadian Standards Association CAN/CSA-S472-92, Foundations, Offshore Structures, and section 5.2.2 of Canadian Standards Association Special Publication S472.1-1992, Commentary to CSA Standard CAN/CSA-S472-92, Foundations.

Structural Strength of Mobile Offshore Platforms

• 55 (1) Every floating platform that is intended to be used in areas in which sea ice is present shall be able to

  • (a) withstand, without major damage, the ice loads to which it may be subjected when it is operating in accordance with the operations manual;

  • (b) stay on location in the ice concentration and under the ice forces to which it may be subjected, as stated in the operations manual; and

  • (c) be moved from the production site or drill site in the ice concentration to which it may be subjected, as stated in the operations manual.

• (2) In an analysis undertaken in accordance with subsection 37(2) for the purpose of determining the resistance to overturning and the resistance to sliding of a self-elevating mobile offshore platform,

  • (a) a lattice type leg may be analysed using equivalent single- beam hydrodynamic coefficients as determined in accordance with Det norske Veritas Classification Notes, Note No. 31.5 — Strength Analysis of Main Structures of Self-Elevating Units, when determining

    • (i) the hydrodynamic loads to be used in calculating overturning forces and sliding forces, if a vertical load equal to 5 per cent of the horizontal load is applied at the centre of the leg, and

    • (ii) the hydrodynamic forces to be used in any detailed finite element analysis of the upper legs and hull;

  • (b) the overturning moments and sliding forces shall be assessed assuming no spudcan fixity and using the most critical combination and direction of environmental and functional loads;

  • (c) the reaction point for an independent leg platform shall be taken as the point located at a distance above the spudcan tip that is equal to the lesser of

    • (i) half the height of the spudcan, and

    • (ii) half the total penetration; and

  • (d) the reaction point for a mat-supported platform shall be determined considering the soil characteristics determined in the site investigation undertaken pursuant to section 46.

• (3) Where any wave frequency or seismic ground motion predicted for the production site of a self-elevating mobile offshore production platform is close to the frequency of oscillation of the platform, a dynamic response calculation shall be performed as part of the analyses required by section 37 and the dynamic loads determined thereby shall be included in the relevant stress and fatigue analyses.

• (4) The connection between each spudcan and each leg of a self-elevating mobile offshore platform shall be designed to withstand without failure the loads occurring at the full spudcan fixity condition.

• (5) Each spudcan and each connection between each spudcan and each leg of a self-elevating mobile offshore platform shall be designed for all possible penetrations or conditions ranging from tip penetration to full spudcan penetration as determined by the site investigation undertaken pursuant to section 46, and the shape of the spudcan.

• (6) Every spudcan of a self-elevating mobile offshore platform shall have sufficient strength to withstand storm-induced horizontal loads, vertical loads, and one half of the lower guide bending moment that is calculated assuming the leg is pinned.

• (7) The secondary bending effects of the legs of a self-elevating mobile offshore platform shall be taken into account in the performance of an analysis pursuant to section 37.

• (8) The analysis required pursuant to section 37 to verify whether a self-elevating mobile offshore platform is capable of withstanding the loads imposed during transportation shall be performed in accordance with Part 3, Chapter 2, Sections 3 C-100 and D-300 of Det norske Veritas Rules for Classification of Mobile Offshore Units.

• (9) A self-elevating mobile offshore platform with independent footing support shall be designed to withstand the loads that may be imposed during preload operations, including where there is

  • (a) loss of foundation support for one leg for a distance of at least 4 m; and

  • (b) offset support of 1.5 m from the centre of the spudcan tip.

• (10) The legs, spudcans and mats of every self-elevating mobile offshore platform shall be designed for any impact load that might occur on setdown, in accordance with Part 3, Chapter 2, Section 3 E-400 of Det norske Veritas Rules for Classification of Mobile Offshore Units, using the maximum environmental and functional loading conditions for setdown operations, as specified in the operations manual.

• (11) The legs of every self-elevating mobile offshore platform shall be preloaded to at least l.l times the reaction expected at the footing or mat at the extreme loading condition.