The self-ignition of charcoal cargoes that had been certified as safe was responsible for fires on two separate boxships, an accident probe has found.

German investigators are now calling existing testing procedures for charcoal to be revised.

Fires were discovered on both Mediterranean Shipping Co’s 13,000-teu MSC Katrina (built 2012) in the Elbe estuary in November 2015; and the Hapag-Lloyd-operated 13,169-teu Ludwigshafen Express (built 2014) in the Red Sea in February 2016.