Design loads as mentioned in the first subsection, comprise functional, environmental and accidental loads, inter alia fire and explosive loads, which form the basis for design and operation of installations, systems and equipment. As regards definitions of the terms design accidental load and dimensioning accidental load, reference is made to
Section 3.
Functional loads as mentioned in the fifth subsection, mean, in the case of load-bearing structures, permanent and variable loads.
Dimensioning loads as mentioned in the third and sixth subsection, comprise functional, environmental and accidental loads, inter alia fire and explosive loads.
In order to fulfil the requirements related to
load-bearing structures, the standards
NORSOK N-001 and
NORSOK N-003 should be used. In addition,
NORSOK N-004 should be used for steel structures.
In order to assess the loss of main safety functions as mentioned in the third subsection, the standard
NORSOK Z-013 Appendix B should be used.
The
NORSOK S-001 standard should be used for
accidental loads, in particular Chapter 5.6, in addition to other standards mentioned in these instructions. Special fire conditions such as jet fires, under-ventilated fires in modules, fire on the sea and the like may require additional calculation of fire loads / actions. For mobile facilities that are not production facilities, and that are registered in a national ship register,
DNVGL-OS-A101 Paragraph 2 can be used as an alternative.
For facilities that are intended to leave the field due to bad weather forecasts, the values for environmental loads connected with the least favourable of the following factors may be used:
- Conditions on the field when moving,
- Conditions during moving,
- Weather conditions at the planned new location, with the specified annual likelihoods in NORSOK N-003.
For mobile facilities registered in a national ship register, the loads that the facility has been exposed to and the expected loads during the period for which the consent for use is applied for, should be taken into account.
To fulfil the requirement regarding loads, load effects, resistance and load combinations, the following standards should be used for
pipeline systems: ISO 13623 Chapter 6 and
DNVGL-ST-F101 Paragraphs 3, 4 and 5 for steel pipelines,
DNVGL-ST-F201 Paragraphs 3, 4 and 5 for catenary metallic risers and API 17J Chapter 5 for flexible pipeline systems.
To fulfil the requirements regarding loads,
NORSOK D-001 Chapters 5 and 6 and
D-010 Chapters 5 and 6 should be used for equipment for conduct of
drilling and well activities and other well-related equipment, for example drilling risers, compensators, well control equipment, completion equipment and intervention equipment.
To fulfil the requirement regarding loads, the
NORSOK standard L-002, Chapter 6 should be used for
pipeline systems in production plants.
If the loads, load effects or resistance factors are uncertain, measurements or model experiments should be conducted to increase the quality of the analyses. The
NORSOK standard N-003 should be used for model experiments on
load-bearing structures.