Detailed offshore design parameters
5.—(1) The total number of offshore platforms within Work No. 1B must not exceed 7, comprising—
(a)up to 4 offshore collector platforms;
(b)1 offshore converter platform; and
(c)up to 2 offshore accommodation or helicopter platforms,
provided that any of the platforms referred to in paragraphs (a) to (c) may be co-joined to create a combined platform fixed to the seabed by multi-leg or gravity base type foundations.
(2) The dimensions of any offshore collector platform (excluding towers, helicopter landing pads, masts and cranes) must not exceed—
(a)75 metres in length;
(b)75 metres in width;
(c)85 metres in height above HAT.
(3) The dimensions of any offshore converter platform (excluding towers, helicopter landing pads, masts and cranes) must not exceed—
(a)125 metres in length;
(b)100 metres in width;
(c)105 metres in height above HAT.
(4) The dimensions of any offshore accommodation or helicopter platform (excluding towers, helicopter landing pads, masts and cranes) must not exceed—
(a)125 metres in length;
(b)100 metres in width;
(c)105 metres in height above HAT.
(5) The dimensions of any combined platform (excluding towers, helicopter landing pads, masts and cranes) must not exceed the total seabed footprint of the individual platforms incorporated within it.
(6) Offshore platform foundation structures must be of 1 or more of the following foundation options: gravity base or multi-leg.
(7) No offshore platform foundation structure employing a footing of driven piles may—
(a)have more than 24 driven piles;
(b)have a pile diameter exceeding 2.75 metres or employ a hammer energy during installation exceeding 1,900 kilojoules.
(8) Within Work No. 1B, the seabed footprint per offshore foundation (excluding subsea scour protection) must not exceed—
(a)in the case of an offshore collector platform, 5,625 square metres;
(b)in the case of an offshore converter platform, 12,500 square metres;
(c)in the case of an offshore accommodation or helicopter platform, 12,500 square metres.
(9) No offshore collector platform foundation may have a seabed footprint (including subsea scour protection) exceeding 9,025 square metres.
(10) No offshore converter platform foundation may have a seabed footprint (including subsea scour protection) exceeding 17,400 square metres.
(11) No offshore accommodation or helicopter platform foundation may have a seabed footprint (including subsea scour protection) exceeding 17,400 square metres.
(12) The number of vessels actively carrying out impact piling as part of the installation of driven pile foundations must at no time exceed 2 within Work No. 1B.