Shedding Light on X-Ray RadiationPosted on March 31, 2017 in Astrophysics Blog
At Astrophysics, Inc., we build and manufacture security scanners that use X-ray radiation to see through objects and find hidden threats.
X-rays, in large doses, can be dangerous. Too much exposure can permanently damage cells, cause cancer, or even death. But how much radiation does an individual need to receive before it is considered dangerous? And, what do harmful levels of radiation look like? There seems to be a lot of confusion on the topic.
It’s important to know that radiation can cause harm; however, when handled properly, X-ray radiation can have a lot of safe and useful applications, many of which are discussed in detail below.
What are X-rays?
X-rays are a type of electromagnetic radiation that is transmitted through waves. Depending on the density of the material they pass through, the waves are absorbed in different amounts. Sophisticated imaging software, like that found in Astrophysics scanners, can translate those wave transmissions into X-ray images.
X-rays are invisible and odorless. You cannot see or smell them, but they are there. In fact, you are exposed to radiation every single day. The amount is so small though, that you do not notice it.
Some natural sources of radiation include: foods with radioactive elements (bananas, lima beans, and carrots*), the earth (minerals and materials buried beneath our feet), the Sun (powered by a continuous nuclear reaction), and the cosmos (high energy radiation from outside our solar system).
X-rays are used in a variety of industries such as medicine, astronomy, security and defense. When used correctly, the benefits of X-ray radiation significantly outweigh any negatives.
What are X-rays used for?
As stated above, there are many practical and safe uses for X-rays. If dentist had a dentist X-ray your teeth or a doctor X-ray a broken bone at the hospital, then you received X-ray radiation. Thankfully, those X-ray machines used are equipped with technology that limits the amount of radiation you receive.
X-ray radiation is often used to examine parts of the body. Besides broken bones and dental records, X-rays can help spot illnesses (pneumonia from a chest X-ray) and cancers (breast cancer from a mammogram). They are used in therapy to kill cancer cells and used in astronomy to detect celestial objects outside of the solar system.
In Astrophysics’ case, we use X-rays to see through objects and detect hidden threats like weapons, explosives, and smuggled items. These objects we see through can be as small as a cell phone and as large as a vehicle. Our X-ray security scanners do all this while emitting very little radiation to operators and nearby persons, helping to keep them safe while they do their jobs.
How do we protect ourselves from X-ray Radiation?
You can protect yourself from unsafe radiation in 3 ways: 1) minimizing exposure time, 2) maximizing your distance from the X-ray source, and 3) using proper shielding. At Astrophysics, Inc., our machines have lead curtains and shielding around the sides of the inspection tunnels. Lead is very effective at blocking gamma rays and X-rays because of its high density and high atomic number. (However, lead can be dangerous to work with too, as it can damage nerves, contaminate the blood, and cause brain disorders. It is important to note that you should
1) minimizing exposure time
2) maximizing your distance from the X-ray source, and
3) using proper shielding.
At Astrophysics, Inc., our machines have lead curtains and shielding around the sides of the inspection tunnels. Lead is very effective at blocking X-rays because of its high density and high atomic number. These safeguards limit the radiation that escapes during scans to the smallest of detectable amounts. (It’s important to remember that lead can be dangerous to work with too – it can damage nerves, contaminate the blood, and cause brain disorders. You should never handle raw lead with bare hands).
What is the likelihood I’ll be exposed to dangerous radiation from X-rays?
The short answer: extremely unlikely. And when you compare radiation exposures across different activities you will understand why.
Randall Munroe’s Radiation Dose Chart helps visualize this. For reference, the universal unit for an absorbed dose of radiation is a Sievert (Sv). One (1) Sv is considered dangerous to humans and two (2) Sv is considered deadly (resulting in severe radiation poisoning). We all absorb small amounts of radiation on a daily basis. The amounts are so small, in fact, that they are usually measure in smaller units: millisieverts (mSv) and micro-Sieverts (µSv).
1 Sievert = 1,000 millisieverts (mSv) = 1,000,000 microsieverts (µSv)
The Environmental Protection Agency (EPA) determined that members of the public should limit their annual radiation exposure to a 1,000 µSv (or 1.0 mSv or 0.001 Sv). For comparison’s sake, the maximum yearly dose permitted for U.S. radiation workers is 50,000 µSv (or 50 mSv or .05 Sv).
Once you know how much radiation a person can safely receive in a year, you can compare it to everyday exposures and past radioactive events:
Based on what we know about radiation, you would have to do the following (in a relatively short period of time) in order to absorb lethal amounts of radiation:
- Eat 800,000,000 bananas
- Fly from New York City to Los Angeles 200,000 times
- Receive 20,000 mammograms
- Spend 1,333 hours walking the grounds at the Chernobyl plant in 2010
At Astrophysics, Inc., our largest vehicle scanners emit less radiation per scan than you would absorb eating a single banana, making them both highly effective and remarkably safe!
Don’t fear the X-ray!
Radiation is a part of life. Our bodies are designed to absorb small amounts of natural radiation on a daily basis. There is no reason to be fearful of an X-ray scan. When used appropriately, X-rays are useful tools that protect us and make our lives much more pleasant.
Interested in knowing your yearly dose of radiation? Check out the Radiation Dose Calculator!