Imagine you are sitting at home with your family on a Sunday afternoon. The weather is beautiful and the birds are chirping. All is well until you hear a noise that sounds similar to a tornado siren. You look outside and see a sunny day with not a cloud in the sky. Your curiosity tells you to turn your local news station on. You find a breaking news report about an iminate bomb detonation at a nearby location. The news reporters are urgently advising people in your area to seek shelter, because there is no time for evacuation. Your heart sinks in your chest. Your first thought is to go to your storm cellar. Your family is in full panic mode as they run to the cellar. The bomb detonates nearby causing wide spread destruction and an extreme change of pressure. The pressure inside your storm shelter can subsequently change too fast and hard causing bodily injury or death to the occupants. The storm shelter salesmen probably won’t tell you not to go into you shelter during such a scenario because he’s concerned about mother-nature and not nearby detonations. Just because you have a underground shelter, that doesn’t mean it was built to guard against every situation.
So what happens inside the shelter? Think of a deep sea submarine submerged thousands of feet below sea level. Imagine a crack in the window shatters causing an extreme change of pressure. That extreme sudden pressure change will cause the submarine to implode. That can give you a pretty good assessment of what could happen to a storm shelter near a detonation.
See how an extreme change of pressure can cause a soda can to implode (Neat science experiment to show the kids). Turn down the volume, and skip to 1:20 in the video. https://www.youtube.com/watch?v=gG5YmkmfCpA
A nuclear weapon (or any large explosion) can cause a shockwave that produces sudden pressure changes several miles away from the point of detonation. If such pressure waves enter a shelter, they will do substantial harm to the occupants and equipment.
How can we make our storm shelter safe from a nearby blast? A set of blast valves is a perfect solution that all good bomb shelters have. A blast valve can be placed on the ventilation pipes to guard against pressure changes. The blast valves are equipped with springs that keep a disk centered away from both entries. Pressure displaces the disk along the axle, until it plugs one entry or the other. After the blast, the springs return the disk to the center and re-open the valve. A blast valve isn’t common with storm shelters. If you have a storm shelter or are thinking about getting a storm shelter, you should definitely keep a blast valve in mind.
Charlotte is involved in production at Rising S Bunkers. Rising S Bunkers manufactures and installs fallout shelters and has been featured on Doomsday Preppers.
EXTRA NOTE – Through December 14th 2014, Rising S Bunkers is giving away a Survival Bunker. Cool deal if you ask me. You can enter at this link.