Effects of Radiation, Harmful Effects of Radiation, Protective Measures (For CBSE, ICSE, IAS, NET, NRA 2022)

Doorsteptutor material for competitive exams is prepared by world's top subject experts: get questions, notes, tests, video lectures and more- for all subjects of your exam.


Radiation can be defined as the transmission or emission of energy in the form of particles or waves through a material medium or space.

This includes:

  • Electromagnetic radiation such as radio waves, heat, x rays, gamma radiation, and even visible light.
  • Particle radiation such as alpha radiation, neutron radiation, and beta radiation
  • Acoustic radiation such as seismic waves, sound, and ultrasound
  • Gravitational radiation

Radiation poisoning occurs when a radioactive material releases particle which enter a person՚s body and cause damage. The different characteristics of the radioactive substances are different. In different ways they can harm and help people and some are more dangerous than others.

Harmful Effects of Radiation

  • Radiation can be non-ionizing or ionizing depending on the radiated particle՚s energy. Radioactive materials that emit radiation are the common sources of ionizing radiation. Visible light, microwaves, infrared light, are the common sources of nonionizing radiation. Both types of radiation are harmful to health even though they have few advantages.
  • Radiation exposure have different effects based on dose received. A key factor in determining the health effects is whether it is chronic or acute. When a dose of radiation is received at once, then it can be called an acute exposure, and when a small dose of radiation is exposed for a long period then it is chronic exposure.
  • Health effects of radiation can be classified into two categories: threshold effects and non-threshold effects. Threshold effects appear after a certain level of radiation exposure is reached and enough cells have been damaged to make the effect apparent. Non-threshold effects can occur at lower levels of radiation exposure.
  • Here are a few common health effects or harmful effects of radiation on the human body.


Loss of hair fall occurs when exposure to radiation is higher than 200 rems.

Heart and Brain

Intense exposure to radiation from 1000 to 5000 rems will affect the functioning of the heart. Radiation kills nerve cells and small blood vessels of heart which may cause immediate death. Brain cells are affected if the radiation exposure is greater than 5000 rems.


Certain body parts are affected specifically when exposed to different types of radiation sources. The thyroid gland may be affected when exposed to radioactive iodine. If exposed to a considerable amount of radioactive iodine, whole or part of the thyroid can be affected.

Blood System

A number of lymphocytic cells present in the blood will be reduced if a person is exposed to 100 rems. This may cause several immune problems. This is termed as mild radiation sickness. As per the reports from Nagasaki and Hiroshima, symptoms may be present more than ten years from that exposure.

Reproductive Tract

As the cells of the reproductive tract divide fastly, these are more prone to be affected even if the exposure is not more than 200 rems.

Protective Measures

  • The objective of radiation protection is to protect people and the environment against the harmful effects of ionizing radiation. This is achieved through a process called risk assessment which involves
    • Identifying the hazard
    • estimating the size of the risk and
    • assessing its importance in comparison with other risks.
  • The results of the risk assessment should be recorded appropriately and used as the basis for making decisions about how to manage the risk. Finally, each risk assessment needs to be reviewed and updated periodically and when new equipment or work practices are introduced.

Developed by: