The world's largest floating crane ship is Thialf, a 201.6 m (661.4 ft) long semi-submersible barge with a lifting capacity of 14,200 tonnes (31.3 million lb). Thialf is operated by Heerema Marine Contractors of the Netherlands. Thialf carries two 95 m (311 ft) tall cranes which are capable of lifting objects in tandem (the lifting capacity quoted above is for such lifts). Essentially a colossal square sea-going barge, the lower section of Thialf's hull can be flooded, increasing its draught (i.e. causing it to float lower in the sea) by 20 m (65.6 ft). This massive addition to the weight of the vessel creates the stability necessary to lift such massive loads, and also allows Thialf to operate in rough seas.There is accommodation for 736 people and a helicopter pad.Width: 88.4 m (290 ft) Depth (bottom of hull to main workdeck) 49.5 m (162 ft) Draught: 11.8 - 31.6 m (38.7 - 103.6 ft) GRT: 136.709 tonnes (standard measurement used in shipping as an indicator of cargo space. No conversion equivalent).