Why The Star Trek Cast Kept Passing Out During Production

Long before it benefitted from modern prosthetics, advanced CGI, or the AR wall, the "Star Trek" franchise did the best it could with what it had. And between moments like Trek's silliest pet the "unicorn dog" Alfa-117 canine in "The Original Series" and the notorious parasite queen death scene in "The Next Generation," the television franchise has certainly seen its share of special effects so bad fans wish they could forget them. But few of the franchise's special effects failures beat the time when the fog used on set was literally making the cast sick and pass out.

The revelation emerged during a 2009 Safety and Health in Arts Productions and Entertainment (SHAPE) Safety Week panel from then-Vice President of Environment, Health, and Safety at NBC-Universal, Paul Jordan, as reported by The Georgia Straight. During the panel, Jordan noted that preventative safety had not been part of the equation during the 1970s and '80s. Without mentioning which set it took place on, the exec brought up a "Star Trek" production where the actors found themselves blacking out on set. They finally realized the problem was due to the liquid nitrogen powering the fog effect they had been using — an effect that quite literally sucked the oxygen from the air.

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.