This document specifies requirements and guidance for the installation on and removal from site of independent leg jack‑up units for use in the oil and gas industries including lower carbon energy. It addresses the assessment of:

a)       the installation operation from when the jack-up enters the defined safety zone of the host platform or the intended site to when it is elevated to the operating hull elevation above LAT and is ready for operations;

b)       the removal operation from when the jack-up is ready to jack-down to when it departs the defined safety zone.

NOTE 1:      Whilst this document is for independent leg jack-up units, many of the provisions can be applied to mat-supported jack-up units.

NOTE 2:      When the jack-up has propulsion assist or is self-propelled the provisions of this standard related to positioning should be replaced or supplemented as appropriate.

The assessment of a jack-up at a specific site is normally comprised of two parts.

1)      Assessing that the unit can survive in the elevated mode.

2)      Assessing that the unit can be safely installed at, and removed from, the site.

Item 1 is addressed in ISO 19905-1 and item 2 is addressed in ISO 19905-4.

Much of the information required for an ISO 19905-1 assessment (referred to herein as a site-specific assessment elevated – SSA-E) is also required for an ISO 19905-4 assessment (referred to herein as a site-specific installation and removal assessment – SSA-I). There is, however, additional information used in an SSA-I that is best gathered at the same time that data for the SSA-E is collected. This is further discussed in 5.1.

This document is for the installation of a jack-up on, and the removal of a jack-up from a site. Specifically excluded from the scope of this document is the move of the jack-up between sites and elevated operations, which are covered by other requirements. This document is structured to consider the issues associated with a particular site and is not necessarily organized in the same way that a jack-up owner or surveyor would develop a rig move procedure (which is normally developed in terms of leaving one site and being elevated at the next), see Figure 1-1. 

Figure 1‑1 — Alignment of specific assessments with multiple sites and rig moves

The provisions of this document form an integrated approach for SSA-I, which is intended to be used in its entirety for the site-specific installation and removal assessment of an independent leg jack‑up.

In this document it is assumed that a site-specific assessment for elevated (survival) operations (SSA-E) is available for the specific site.