After a nuclear explosion, how long should you stay on the deck?

Staying on the deck for 90 seconds after a nuclear explosion is recommended to allow for the immediate fallout to disperse. This period is designed to minimize the exposure to nuclear radiation that may still be present in the initial moments following the explosion.

The rationale behind this specific duration is informed by understanding the effects of nuclear blasts and the behavior of radioactive materials post-explosion. During the first few moments, the intensity of the radiation decreases, and significant doses can be avoided by waiting for a short period. This time frame enables individuals to prevent unnecessary exposure while ensuring they can eventually move to a safer location.

In scenarios where individuals might remain exposed for shorter or longer periods, there could be increased risk or insufficient time for protective actions to take effect adequately. Hence, the designated 90 seconds serves as a well-considered compromise for maintaining safety in these critical moments post-detonation.