John S. Barry, an executive who masterminded the spread of WD-40, the petroleum-based lubricant and protectant created for the space program, into millions of American households, died on July 3 in the La Jolla neighborhood of San Diego. He was 84.

The cause was pulmonary fibrosis, a lung disease, said Garry Ridge, president and chief executive of the WD-40 Company.

The company says surveys show that WD-40, the slippery stuff in the blue and yellow aerosol can, can be found in as many as 80 percent of American homes and that it has at least 2,000 uses, most discovered by users themselves. These include silencing squeaky hinges, removing road tar from automobiles and protecting tools from rust.

Mr. Barry was not part of the Rocket Chemical Company in 1953, when its staff of three set out to develop a line of rust-prevention solvents and degreasers for the aerospace industry in a small lab in San Diego. It took them 40 attempts to work out the water displacement formula. The name WD-40 stands for “water displacement, formulation successful in 40th attempt.”