 A 20-berth auxiliary accommodation compartment (the 'austere' compartment) was included in the design, for the transportation of soldiers, illegal fishermen, or unauthorised arrivals; in the latter two cases, the compartment could be secured from the outside.However, a malfunction in the sewage treatment facilities aboard in August 2006 pumped hydrogen sulphide and carbon monoxide into the compartment, non-fatally poisoning four sailors working inside.Use of the compartment as accommodation was banned across the class, and is still in effect as of January 2014.