Bill Jones, 67, cannot walk up stairs without getting breathless and is given two hours of oxygen treatment a day. He claims his health troubles were caused by inhaling the toxic powder while working for the firm in the late 1960s and early 1970s.
He was using a drilling chemical called Flosal, which may have contained up to 95 per cent powdered asbestos.
The father-of-two, from Knowsley, Merseyside, said: "The dust I was exposed to was in such great volumes that, often after emptying sacks of Flosal, the room became a swirling mass of dust as the powder billowed up. My colleagues and I looked like snowmen within minutes."
Shell declined to comment on the case as it is the subject of ongoing litigation.