And do not forget a brave cosmonaut...
...who entered an oxygen-rich test chamber, prior to Vostok 1, and also died as a result of a fire due to the
excessive oxygen in the experimental
chamber.
The name of that brave cosmonaut escapes me, but like the lessons learned from the Apollo-1 tragedy, that cosmonaut's death provided Soviet space engineers with a tragically learned lesson which has led to Soviet designs of sealevel pressures with 80%N2/20%O2 gas ratios onboard Russian manned spacecraft, that have proven safe over 40 years.
Jacob