Investigators determined that the poor management of the Apollo 1 capsule’s design and construction had directly contributed to the deaths of the astronauts during the 17 second period in which the fire was reported and the explosion of the vehicle. The vehicle itself was poorly documented, which made it difficult to determine exactly what had gone on during the building process. Of the many different safety concerns cited, the chief amongst them was the decision to use a pressurized, 100% pure oxygen environment instead of the nitrogen / oxygen mixed breathed on Earth. At the pressures that the capsule was running during the test , the 3.2 square meters of Velcro installed in the capsule ran the risk of spontaneously exploding. Static discharge between the nylon space suits and the nylon materials used to construct the seats in Apollo 1 were also highlighted.
A complete re-design of the Apollo project’s command modules was undertaken which addressed all of these concerns. To make escape more feasible, the escape hatch was built to open outwards, and quickly. Wiring was properly insulated, flammable materials were removed, and the oxygen / nitrogen mix and pressure would be carefully adjusted throughout the mission.