Apollo continued to use pure oxygen once in space, even after the Apollo 1 fire. https://www.popsci.com/why-did-nasa-still-use-pure-oxygen-after-apollo-1-fire/

Apollo continued to use pure oxygen once in space, even after the Apollo 1 fire. https://www.popsci.com/why-did-nasa-still-use-pure-oxygen-after-apollo-1-fire/ https://www.popsci.com/why-did-nasa-still-use-pure-oxygen-af...