Abstract: A moon pool control device (5) for a marine vessel (1) comprises one or more closure members (8a,b) arranged for movement in the moon pool, between a moon pool closing position in a region of the moon pool opening (7), a moon pool open position, and a retracted position, and guiding means (14a,b; 15a,b; 17a,b; 18a,b) and motive means (9a,b; 10a,b; 22) configured for moving the closure member between said positions. In a particular embodiment, a pair of closure members (8a,b) and corresponding guiding means (14a,b; 15a,b; 17a,b; 18a,b) and motive means (9a,b; 10a,b; 22) are arranged on opposite lateral sides of the moon pool and configured to cooperate to close the opening (7) when both closure member s are in the closing position. The closure members comprise a continuous surface that forms a fluid barrier. The closure members may be retrieved onto the deck of the vessel.

Abstract: A moon pool control device (5) for a marine vessel (1) comprises one or more closure members (8a,b) arranged for movement in the moon pool, between a moon pool closing position in a region of the moon pool opening (7), a moon pool open position, and a retracted position, and guiding means (14a,b; 15a,b; 17a,b; 18a,b) and motive means (9a,b; 10a,b; 22) configured for moving the closure member between said positions. In a particular embodiment, a pair of closure members (8a,b) and corresponding guiding means (14a,b; 15a,b; 17a,b; 18a,b) and motive means (9a,b; 10a,b; 22) are arranged on opposite lateral sides of the moon pool and configured to cooperate to close the opening (7) when both closure member s are in the closing position. The closure members comprise a continuous surface that forms a fluid barrier. The closure members may be retrieved onto the deck of the vessel.