Steve Sullivan worked in the Development Division of Frankenstein and Sons Ltd, a waterproof clothing manufacturing company based in Manchester. Along with his colleague Ian B Wright, Sullivan was involved in the designing and testing of a full pressure suit in collaboration with A V Roe & Co Ltd and the Aeroplane and Armament Experimental Establishment at Boscombe Down. The suit was intended for use by pilots of the Royal Air Force Bomber Command flying V Bombers at very high altitudes. The development of ultra high altitude protective clothing came to an end in Britain when the V-Bomber force operations changed to relatively low altitude interdiction.

Founded in 1854 by Philip Frankenstein, P Frankenstein & Sons Ltd was a textiles company located at the Victoria Rubber Works in Newton Heath, Manchester, which specialised in working with rubberised fabrics. It was incorporated as a limited company in 1925 and was popularly known as Frankenstein's. The company manufactured rubber proofed piece goods, rubberised hospital sheetings, and rubber proofed and Gabardine raincoats. From the 1940s, it began producing inflatable lifesaving equipment and protective clothing, including specialised safety and survival equipment for the aviation industry. In 1959, the company produced a prototype high pressure flying suit that circulated liquid through pipes incorporated within the clothing. Frankenstein's worked on the high pressure suit with another Manchester company, Baxter, Woodhouse and Taylor, which developed the seals between the high pressure suit and the helmet. The Frankenstein high pressure suit was used by NASA in trials to develop the spacesuit worn by astronauts in the Apollo missions. In 1963, Frankenstein's acquired another Manchester-based rainwear manufacturer, Baracuta (Clothiers), expanding their production operations. In 1968, Frankenstein's made the iconic yellow spacesuits worn in the Stanley Kubrick film "2001: A Space Odyssey" By 1970, Frankenstein's was underperforming and was acquired by the investment company Slater, Walker Securities as part of their Allied Polymer Group. Allied Polymer Group separated from Slater, Walker Securities in 1971, taking Frankenstein's and two other companies with it.