In the vast majority of action movies, the hero is searching for a villain who is looking to use some sort of nuclear powered radioactive weapon to wreak havoc on mankind. While most people intuitively understand the idea that radiation is dangerous, many do not thoroughly understand why it is so dangerous.
Radiation is made of various subatomic particles. These include alpha particles, neutrons, and gamma rays. All of these particles travel through space at unfathomably fast speeds. Some of them reach speeds in excess of 100,000 miles every single second. Because of this speed, when these particles come in contact with the human body, they do not only hit the exterior surface, instead they penetrate deep into the body. These particles have the power to interrupt and damage the basic building blocks of the human body. The result of this damage is that cancer may develop. Or if the damage is done to a person’s reproductive cells, it can have genetic effects on their future offspring. This simplistic summary of what radiation can do to the human body makes it very clear why it is so dangerous and why large amounts of radiation must be avoided.
It is important to emphasize the fact that large amounts of radiation are what causes damage. Daily people are hit by more than 15,000 particles of radiation every second. This means that in a person’s lifetime, they are hit with 40 trillion particles of radiation throughout their life, and this is just from natural sources. Add onto that the x-rays a person gets when they go to the doctor, which on their own bombard the body with trillions of particles of radiation, and it becomes clear that radiation is a part of everybody’s life. Yet, not every single person is dying of cancer.
The danger has less to do with the amount of radiation a person is exposed to and more to do with the chance of radiation exposure triggering the chain reaction that leads to cancer. For every particle of radiation a person is exposed to, they have a 1 in 30 quadrillion chance of getting cancer. So, if a person was very unfortunate, just getting hit by one particle of radiation could lead to cancer. The thing is that the more times a person is exposed to radiation particles, the higher the chance of them eventually getting cancer. For this reason, EMF meters are used to determine if there are dangerous levels of radiation in an area and provide people with the warning they need.