Every jack-up shall have adequate s

Every jack-up shall have adequate structural strength, overturning stability and
foundation capacity to withstand any combination of environmental conditions to which the jack-up may be subjected while elevated at a specified location. Account shall be taken of the properties and characteristics of the seabed and subsoil to ensure there is adequate resistance for applied loads. If rotational foundation fixity can be justified this may be included in appropriate structural analysis.

Self-propelled jack-ups
Self-propelled jack-ups considered in these guidelines shall be defined as power driven vessels capable of undertaking sea passages within their certified trading area under their own power and without tug assistance. Such vessels shall be assigned an appropriate class notation signifying their type and capability.

The proposed tug(s) shall be in satisfactory condition. The tug(s) and towing equipment, machinery, manning and fuel requirements shall be suitable for the proposed operation. Certification and documentation required by the Flag State shall be in order, and the tug(s) shall be classed by a Recognised Class Society or certified under the provisions of the MCA Small Commercial Vessel and Pilot Boat (SCV) Code (as currently set out in MGN 280) or foreign equivalent.

The tug(s) shall be provided with a Bollard Pull Test Certificate stating the
continuous (sustained) bollard pull based upon a bollard pull test carried out within the last ten years.

All towing equipment shall be in satisfactory condition. Test certificates for all
items shall be valid and shall be available for inspection, with clear means of identification of the respective equipment.

The towing vessel shall have a spare towline that shall be similar in all respects to
the main towline. Where the spare towline is not spooled on to a second winch drum, it shall be stowed in such a manner that it can be spooled on to the main towing drum by the crew at sea.

Bollard pull requirements
The total environmental load acting on the jack-up and cargo due to the combined effects of the following conditions shall be calculated, and the minimum towline pull required (TPR) should be calculated to hold the jack-up at zero forward speed in a fully developed gale, defined as:

Significant wave height (Hs): 5 metres
Wind speed: 20m/s (approx. 40 knots) Current: 0.5m/s (approx. 1 knot).

Towing winches
Towing vessels shall be fitted with a suitable towing winch. Towing from a towing hook will not be accepted for open-sea passages but may be accepted for harbour moves or movements in inshore sheltered waters.

Two towing drums shall normally be provided. Where a second towing drum is
not fitted, then means of reconnection of the spare towline shall be supplied.
The spare towline shall be in good condition and of the required strength. There must be suitable means for connecting the line to the tug and making a rapid reconnection to the emergency towline on the towed barge.

The tow winch shall have a minimum holding power of three (3) times the static
bollard pull of the tug at the inner layer on the drum.