47337 passes Mostyn on 30 March 1991 with the 7F18 Llandudno Junction to Ellesmere Port chemical tanks, unusually running on a Saturday. The train, which had originated at Associated Octel terminal at Amlwch, on Anglesey, is conveying both full and empty tanks. The four grey tanks at the front of the train are conveying ethylene dibromide, which was used in the manufacture of anti-knock compound for petrol. The white chlorine tanks are empty, having previously brought chlorine to the Amlwch plant to be used in the process of extracting bromide from sea water. The two brake vans and barrier wagons were used on this train due to the hazardous nature of the load.