‘Ionizing radiation’ might sound like something from a sci-fi movie. However, it is something we experience every day, only we might not know about it.
A little bit scientifically
Ionizing radiation is a type of energy released by atoms in the form of electromagnetic waves or particles. It’s powerful enough to remove tightly bound electrons from atoms, creating ions, hence the name ionizing. It can also be powerful enough to damage DNA structure. Therefore, prolonged exposure to elevated levels of ionizing radiation is linked to various health risks1, including elevated risks of cancer2.
But where is it, really?
Radiation isn’t confined to nuclear power plants or medical X-ray machines; it’s all around us. Naturally occurring radioactive materials are present in the earth’s crust, for example, granite. Also, cosmic rays bombard us from outer space all the time. Most of us will encounter ionizing radiation only as a normal background radiation1 which is always present in the environment. It includes, mentioned cosmic radiation which comes from the sun and stars. However, sometimes we as humans add to this normal background radiation through activities like flying at high altitudes, living in buildings made of certain materials, undergoing medical procedures like CT scans, or having a particular interest in vintage radium clocks and glass.
The importance of monitoring
Monitoring ionizing radiation isn’t just a matter of scientific interest; it’s a good health and safety practice. While radiation has beneficial applications, such as in medical treatments and energy production, its ionizing form can pose significant risks to living organisms. Prolonged or intense exposure can damage biological tissues, leading to health issues like cancer and genetic mutations.1 By keeping tabs on radiation levels, we can manage these risks, ensuring that the benefits of radiation are harnessed safely and effectively.
When it comes to radiation, two key metrics are essential: dose rate and total dose. The dose rate is like the speedometer on a car, telling us how fast we’re “accumulating” radiation at any given moment. In contrast, the total dose is the cumulative amount of radiation absorbed over time, akin to the odometer’s reading. Understanding both helps in assessing exposure and implementing safety measures.
Measuring dose rate and total dose is crucial for several reasons. Firstly, it enables us to evaluate the immediate risk of exposure in a specific environment, guiding us in applying the principles of time, distance, and shielding effectively. Secondly, by tracking the Total dose one can monitor exposure over time, making informed decisions to minimize health risks.
Some typical numbers
On an everyday basis, we use various units and measurements. We know that 77 F (25 C) is a relatively warm room or that 8kg is too much for a typical house cat. But how to know how much radiation is bad if it is something we can’t feel?
The answer is simple- using a Radiation sensor. The impact of ionizing radiation on health can differ based on the radiation’s type and energy, the length of exposure, and which part of the body is exposed. This impact is known as the effective dose, quantified in Sieverts (Sv). A single Sievert represents a substantial amount; therefore, typical radiation doses are measured in milli-Sieverts (mSv) or micro-Sieverts (µSv).
Some interesting facts in numbers for context:
- One chest X-ray will give about 0.05 to 0.1 mSv of radiation dose.3
- The highest observed background levels are around 0.2 µSv/h, or translated to the annual Total dose: 2.5 mSv.3,4,5
- The 100 mSv/year is the occupational limit which must not be exceeded for more than 5 consecutive years as per German government regulations.6
- NASA’s Standards state that individual crewmember’s total career effective radiation dose during spaceflight radiation exposure must be smaller than 600 mSv.7
How can I protect myself?
Protection from ionizing radiation is based on three key principles: time, distance, and shielding.8 Minimizing the time spent near sources of radiation, maximizing the distance from such sources, and utilizing materials that block radiation effectively are all straightforward yet powerful ways to reduce exposure. Awareness and education are the first steps toward effective protection.
Bibliography
- Risks associated with ionizing radiation: Environmental pollution and health, British Medical Bulletin, Academic journal article [URL].
- Cancer Causes and Prevention, Risk Factors, Radiation, NIH-National Cancer Institute [URL].
- Health Effects of Ionising Radiation on People, National Environment Agency of Singapore [URL].
- EURDEP Gamma Dose Rates Advanced Map, Joint Research Centre of the European Commission [URL].
- Radiation Thermometer, CDC – Centers for Disease Control and Prevention [URL].
- Limit values in radiation protection, The Federal Office for Radiation Protection (BfS) of Germany, accessed 23 October 2023 [URL].
- NASA-STD-3001 Technical Brief, accessed 21 March 2024 [URL].
- Ionizing Radiation, Occupational Safety and Health Administration, accessed 21 March 2024 [URL].