Shipbuilding; Providing information relating to shipbuilding; Naval shipyard services; Construction of prospecting platforms; Plumbing; Maintenance of plumbing; Maintenance and repair of gas and electricity installations; Installation of fire extinction systems; Maintenance of fire alarm installations; Providing information relating to the repair or maintenance of fire alarms; Maintenance and repair of fire extinction systems; Installation, maintenance and repair of air-conditioning apparatus; Installation, repair and maintenance of heating equipment; Advisory services relating to the installation of heating and cooling apparatus.;