The issue of Ted's last name, Crisps, mistakenly becoming Chips may reffer to more than the novella and movies "Goodbye, Mr. Chips". In England what we call French fries are called chips, and what we call potato chips are called crisps.
Lem wants to know if the jet pack's " hydrogen/oxygen ratio is below the burn flash point". Garbled concepts. The range of ratios of hydrogen and air, at normal conditions, that can support combustion is 4% to 74%. The flash point is the temperature at which these mixtures ignite, about 1000°F give or take about 50 degrees.