Matt Whiting wrote:

Richard Lamb wrote:

In the aftermath of the Apollo 1 fire, NASA took a year (and $75 mil)
to redesign the space craft, mature their mental attitudes, and yes,
did come back with a much safer vehicle.

Yes, but I still wonder how anyone in their right might would use a
nearly pure oxygen atmosphere in a vehicle full of humans and electrical
equipment...

Matt

Probably because it might be possible to run at a lower pressure
in flight and keep the crew alive.

This _was_ one of the very first corrections made to the design.
60% O2 /40% N