Hais arose from a proposal originated by Clifford Hartley, the chief engineer with the Anglo-Iranian Oil Company, for a flexible pipe with a lead core that could be laid by a cable-layer ship. It was known as Hais after its developers, Hartley-Anglo-Iranian-Siemens, and was tested in December 1942 by running a cable pipeline across the Bristol Channel from Swansea to Watermouth. The design was so successful it was decided to upgrade it from 2 to 3 inches (5.1 to 7.6 cm) in diameter.