Study decodes how to shelter from nuclear explosion

‘Before the study danger to people inside a concrete-reinforced building that withstands the blast wave was unclear’

Scientists have revealed the preferential areas in rooms where people can avoid the risk of exposure to supersonic shock waves from a nuclear explosion, an advance that may guide the future design of buildings in conflict zones.

Researchers, including those from the University of Nicosia in Cyprus, the nuclear blast effects on humans inside a building within a moderate damage zone.

While objects and humans very close to the explosion are instantly vaporised, and radiation can also pose serious health threat even at a distance, the new study, published on Tuesday in the Physics of Fluids, examined the risk from blast waves generated when nuclear bomb goes off.

In the study, scientists simulated an atomic bomb explosion from a typical intercontinental ballistic missile and the resulting blast wave to understand how it would affect people sheltering indoors.

While the blast wave from such an explosion in a moderate zone can topple some buildings and injure people outdoors, sturdier concrete buildings can remain standing, they say.

Scientists simulated how a nuclear blast wave speeds through a standing structure with features including rooms, windows, doorways, and corridors.

They calculated the speed of the air following the blast wave to determine the best and worst places to be.

“Before our study, the danger to people inside a concrete-reinforced building that withstands the blast wave was unclear,” said study author Dimitris Drikakis.

“Our study shows that high airspeeds remain a considerable hazard and can still result in severe injuries or even fatalities,” Dr Drikakis said.

The study found that simply being in a sturdy building even in a moderate damage zone is not enough to avoid life threatening risk.

Tight spaces in buildings can increase airspeed, and the involvement of the blast wave can cause air to reflect off walls and bend around corners, researchers say.

In the worst scenarios, they say this effect can produce a force equivalent to 18 times a human’s body weight.

“The most dangerous critical indoor locations to avoid are the windows, the corridors, and the doors,” said Ioannis Kokkinakis, another author of the study.

“People should stay away from these locations and immediately take shelter. Even in the front room facing the explosion, one can be safe from the high airspeeds if positioned at the corners of the wall facing the blast,” Dr Kokkinakis said.

Since the time between the explosion and the arrival of the blast wave is only about 10 seconds, researchers say quickly getting to a safe place is critical.

“Additionally, there will be increased radiation levels, unsafe buildings, damaged power and gas lines, and fires. People should be concerned about all the above and seek immediate emergency assistance,” Dr Drikakis said.

Researchers believe understanding the effects of a nuclear explosion can help prevent injuries and guide rescue efforts and aid in the future design of concrete structures.