Abstract: The present invention relates to a device for passively reducing the noise vibrations in a liquid resulting from a sound source (62) which is arranged below the liquid level of a body of water (w), the device comprising a noise-insulating pipe (1) which is designed to be arranged around the sound source, wherein the pipe comprises a number of telescopically extendable and retractable pipe sections, (2,3,4) fastening means for attaching at least one first and one second pipe section to one another in extended and/or retracted position, wherein the fastening means are designed to allow the mutual displacement of the pipe sections in a starting position and to attach the pipe sections to one another in a fastening position, and wherein the fastening means are also designed to keep the first (2) and second pipe sections (3) substantially acoustically disconnected in the fastening position.

Abstract: The present invention relates to a device for the passive reduction of the sound vibrations in a liquid resulting from a sound source arranged below the liquid level of a body of water, the device comprising an elongate tube which can be arranged over the sound source, the tube comprising an outer wall and inner wall, wherein the tube is designed to maintain a certain desired pressure in the intermediate space between the inner and outer wall. In this case, the pressure is reduced with respect to the ambient pressure. As a result of the reduced pressure, the sound vibrations will less readily travel to the outside and the noise level in the area around the tube is reduced.

Abstract: The invention relates to a template (10) for use in installing a plurality of foundation elements, in particular anchor piles (3), relative to one another in an underwater ground formation (2). The template (10) comprises a plurality of guides (11) for the foundation elements (3), which guides (11) are fixed relative to one another by means of a frame (12). At least one of the guides (11) comprises a sound-insulating sleeve (11A) for surrounding a foundation element (3) during driving.

Abstract: The invention relates to a method of installing foundation elements, in particular (mono)piles (2), in an underwater ground formation (3), by means of a driver (4), comprising the steps of placing a foundation element (2) on the underwater ground formation (3) and holding the foundation element (2) in place by means of a gripper (10) mounted on a surface vessel, placing a sleeve (6) for reducing noise input from the driver (4) about the foundation element (2), disengaging the gripper (10), lowering the sleeve (6) onto the ground formation (3), and placing the driver (4) on top of the foundation element (2). The sleeve (6) is held at least laterally with a guide (11) mounted on the surface vessel, at least when disengaging the gripper (10).