Why The Star Trek Cast Kept Passing Out During Production

For decades, issues with movie and TV set fog causing hypoxia were common. Traditionally, liquid nitrogen or dry ice were used to achieve the fogging or misting effect on set, which could literally cause anyone who happened to be on the soundstage to become hypoxic before fainting from oxygen deprivation. At the time, Hollywood’s best solution for managing the pain point was to simply shut down the set temporarily so it could be completely aired out only to be refogged again later — not a great option in an industry where time is money.

But in 1998, Warner Bros. decided it was time for a change, prompting the studio to reach out to industrial gas guy and “Star Trek” fan Jim Foley of Praxair Inc. A large-scale gases and industrial engineering company, Praxair was responsible for supplying things like oxygen to hospitals, hydrogen to refineries, and specialty gases to electronics plants. If anyone could create a product that didn’t leave the actors with lasting injuries they got on set, it was them.

After a six-month process, a much safer solution was devised. Called Liquid Synthetic Air, the fog they developed uses a liquid nitrogen and liquid oxygen combination that doesn’t induce asphyxiation. Its use in 1997’s “Batman & Robin” was proof of concept, earning Praxair an Academy Award for Outstanding Technical Achievement the following year. It was a huge shock for the Trek fan behind the product, who told the Wall Street Journal, “Never in a million years did I think this would happen to me.” But Foley was quick to add that his fog has yet to be used in the Trek franchise.

If you enjoyed this story, check out our piece on the biggest on-screen mistakes in “Star Trek” shows.