Millions of people are exposed to radiation globally everyday. This is beacuse radiation is used in a diverse range of industrial, medical and communication technologies. Although these technologies are beneficial to people living across the globe, radiation exposure can have harmful effects on human health. There are many common sources of radiation we are exposed to daily, thus it is important to identify radiation safety techniques.

What is Radiation?

According to the United States Department of Labour, radiation is defined as energy travelling through space. There are two main types of radiation: non-ionizing radiation and ionizing radiation.

  1. Non-ionizing radiation consists of optical radiation (ultraviolet, visible and infrared) and electromagnetic fields (power frequencies, microwaves and radio frequencies)

  2. Ionizing radiation occurs as either electromagnetic rays (x-rays and gamma rays) or particles (alpha and beta particles)

Measurement and Exposure Limits

Radiation is measured in rem. The millirem, abbrevaited mrem, is the unit used to measure the effect of radiation on the body. The mrem also takes into account the differences in the various types of radiation. According to the U.S. Environmental Protection Agency (EPA), man-made sources of radiation should not exceed 4 mrem per year. For individuals working around radiation full time, males 18 years and over should not be exposed to more than 5 rem per year; and pregnant women should not be exposed to more than 500 mrem during pregnancy.

Effects of Radiation Exposure on Human Health

The nature and extent of the effects of radiation on the human body are dependent on the exposure levels, the frequency of the exposures, and the penetrating power of the radiation. The effects of radiation can be of two types: deterministic and stochastic.

  • Deterministic: Deterministic effects occur at the organ level. If a sufficient number of cells become affected, the organ is not able to function and becomes impaired. Further, the effects of the radiation are not noticeable until the absorbed dose is greater the threshold level. Therefore, deterministic effects are manifested soon after exposure and include: radiation skin burning, blood count effects and cataracts

  • Stochastic: Stochastic effects occur at the cellular level. They are caused by more subtle radiation-induced cellular changes, such as DNA mutations. For these effects to occur, radiation exposure must be random in nature with no threshold dose. Cancer is the only observed clinical manifestation of radiation-induced stochastic effects

9 Common Sources of Radiation in the Home and Workplace

  1. Television sets: The average person watches approximately 4.5 hours of television per day, acquiring 1 mrem of x-ray radiation. Television sets that contain cathode ray tubes can generate low-level x-rays

  2. Computer monitors: Similar to television sets, computer monitors that contain cathode ray tubes also generate low-level x-rays

  3. Drinking water: Your drinking water may contain radiation. In urban areas, radiation comes from rivers and lakes while in rural areas, radiation comes from wells. Water can pick up radiation from natural sources, such as rocks and soils. Therefore, the average person can acquire up to 5 mrem of radiation from drinking water per year

  4. Natural gas: Natural gas used for cooking and heating may increase your exposed to radiation by up to 9 mrem per year

  5. Cellphones: Cellphones give off radio frequency waves with the average person acquiring 11 mrem of radiation per year. Fortunately, the radio frequency waves generated are at low enough levels and therefore, do not cause damage to cells or tissues

  6. Microwave ovens: Microwave ovens emit radio frequency electromagnetic energy. Some studies have indicated that microwave energy may leak from your oven while in use but will not have any negative health impacts if your microwave is properly maintained

  7. Soils: Radioactive particles in the soil are released in the form of gases which we either inhale or gets taken up in water and plants. Therefore, the average person acquires 35 mrem of radiation per year from soils. These radioactive particles are present in the soil due to cosmic radiation in the the Earth's crust or are absorbed from man-made releases such as nuclear power plant disasters

  8. Radon gas: Radon is the second leading cause of lung cancer in the United States. It is emitted from the radioactive decay of natural uranium in the ground. It can also be found in some construction materials. This radon becomes trapped in buildings and as such, the average person may acquire up to 200 mrem per year

  9. Cigarette smoke: Smokers are not only increasing their risk of lung cancer and heart disease everytime they take a puff, they are also increasing their exposure to radiation. It is estimated that the average smoker acquires 1,300 mrem of radiation per year from radioactive material found in the fertilizers used on the tobacco plants, as well as other natural sources

General Safety Tips to Avoid or Reduce Radiation Exposure

  • Consider switching to flat screen television sets and computer monitors. These do not contain cathode ray tubes and therefore, would not produce x-ray radiation

  • Opt for bottled water over tap water. While both may contain radiation, the levels of radiation in bottled water would be far less

  • Although radiation levels from cellphones are extremely low, to reduce radio frequency waves near your body you can: (a) get a hands-free headset which connects directly to your phone or (b) use speaker-phone more often

  • Keep your exposure to microwave energy at a minimum by keeping your microwave oven in good working condition

  • You cannot see or smell radon but it is not difficult to determine if you have a radon problem in your home or workplace. All you need to do is test for radon using any low-cost do-it-yourself radon testing kit found at any hardware store

  • Consider changing your smoking habits

The Importance of Radiation Safety

Radiation is invisible and odourless. Thus, it is easy to become complacent about the dangers of radiation. As a result, we expose ourselves and those around us to higher levels of radiation than necessary. Therefore, following best radiation practices is beneficial to both you and your loved ones.