Her name alluded to the role Sigyn played in holding a cup over the fettered Loki, catching the venom dripping from a viper perched above him.

Sigyn was built in 1982 by the French Société Nouvelle des Ateliers et Chantiers du Havre at Le Havre,[2] and could transport up to ten containers for spent fuel or radioactive waste.

A stern ramp enabled roll-on/roll-off loading and unloading[3] from the 59 m (194 ft) long cargo deck.

[2] Sigyn was owned by Svensk Kärnbränslehantering AB (SKB) (Swedish Nuclear Fuel and Waste Management Company), but was operated and staffed by Furetank Rederi AB (Furetank Shipping Company)[3] In December 2010 it was announced that SKB have ordered a new ship from the Dutch Damen Group to replace Sigyn.

[4] The new ship named Sigrid,[5] was laid down in Galați, Romania, in December 2011, and was delivered in May 2013.