Taking cover in existing buildings is widely accepted as a critical first action after a nuclear blast in a major city.
But how long people should stay there before moving to better shelter is a more complex question.
Buildings that are lightweight or lack a basement are more easily penetrated by radioactive dust.
Writing in a British scientific journal, Michael Dillon of the Lawrence Livermore National Laboratory in California, has now come up with a mathematical model for the “optimal shelter exit time” to minimise radiation risk.
Based on his calculations, if adequate shelter is 15 minutes away, individuals should remain in their initial, poor-quality shelter no longer than 30 minutes after detonation.
If, however, the better shelter is only five minutes away, individuals should move there immediately and forego the closer but unsafe buildings altogether, he wrote.
Read more at: Phys.org