This blog post examines the dangers radiation poses to the human body and how we can safely protect ourselves from it.

Introduction

In March 2011, the Fukushima nuclear power plant accident drew global attention and concern, once again highlighting the dangers of radiation. In South Korea, geographically close to Japan and separated only by the sea, awareness of these dangers is inevitably heightened. However, some excessive fears about radiation, much like the past mad cow disease (bovine spongiform encephalopathy) incident, often stem from vague anxieties rather than rational judgments based on information. A proper understanding of radiation and the rational radiation protection based on it are becoming increasingly important.

What is radiation?

Radiation refers to high-energy electromagnetic waves, essentially light possessing immense power. It typically denotes ionizing radiation, which carries sufficient energy to ionize atoms. The terms ‘radiation’, ‘radioactivity’, and ‘radioactive’ can be confusing here. Radiation (放射線) refers to the rays emitted from a light source, radioactivity (放射性) denotes the property of emitting radiation, and radioactivity (放射能) signifies the ability to emit radiation. Radioactive substances emit radiation commensurate with their radioactivity, and the danger of radiation primarily stems from its high energy.
The energy of radiation can cause ‘ionization’ within living organisms and structures. Ionization is the process where atoms or molecules transform into charged ions, breaking bonds. Within living organisms, this can cause damage from exposure, such as genetic abnormalities and infertility. Conversely, this property is intentionally utilized for medical and industrial processes like gamma ray sterilization and radiation cancer therapy.

Historical Background of Exposure and Radiation Protection

The concepts of radiation exposure and radiation protection began to emerge in the late 19th century. On November 8, 1895, Röntgen discovered X-rays, initiating research utilizing them. As the properties of X-rays were studied, the necessity for radiation protection became apparent. In 1902, efforts began to establish exposure limits for individuals working with X-rays, and by 1906, basic guidelines for radiation protection were established. However, the necessity of radiation protection was not widely recognized at the time, and research on the effects of radiation on the human body was insufficient.
In 1921, the British Röntgen Society publicly highlighted the dangers of radiation exposure and issued an official statement. In 1922, the American Röntgen Society published recommendations on radiation exposure. Research related to radiation protection continued in several countries, including France, Germany, the Netherlands, the Soviet Union, and Sweden, until the mid-1920s. Currently, the IAEA (International Atomic Energy Agency) and the ICRP (International Commission on Radiological Protection) establish and manage radiation protection standards. The ICRP considers radiation above natural levels potentially harmful, but deems it safe within appropriate limits because the use of ionizing radiation is essential for human progress.

Principles of Radiation Protection

Current radiation protection standards follow three principles. First, radiation exposure should be avoided whenever possible. Second, all exposure should be minimized, considering economic and social conditions. Third, the radiation dose received by an individual should not exceed levels that could cause non-stochastic effects.
Radiation exposure standards are broadly categorized for radiation workers and the general public. Standards for radiation workers have evolved from the ICRP’s tolerable dose in 1934, the NCRP’s maximum permissible dose in 1946, and the FRC’s radiation protection guidelines in 1960, to the current ICRP’s lowest achievable level. Throughout this process, the standards have progressively decreased. For the general public, standards remain significantly lower than those for radiation workers. This is because, unlike for workers, societal benefits are not considered in setting these limits.

Radiation Protection in Practice

Radiation protection aims to control the limited use of radiation. It focuses on preventing leaks of radioactive materials and, if a leak occurs, on rapid containment and minimizing harm. Monitoring of radioactive materials is divided into four categories: process monitoring, area monitoring, emission monitoring, and environmental monitoring. This monitoring focuses on ensuring radioactive materials do not exceed specified limits.
If a radioactive material leak or radiation exposure situation occurs, damage can be minimized through the following three methods. First, maintain sufficient distance from the radiation source. Second, install shielding. Third, minimize exposure time.

Internal Exposure and Decontamination

When internal exposure or environmental leakage occurs, standard radiation protection methods are insufficient. In such cases, radioactive materials are classified based on whether the contamination source can be removed. Particularly important are removable contaminants like radioactive fallout, which can directly enter the body. The process of removing these contaminants is called decontamination, and various decontamination methods are adopted based on the physical and chemical properties of the contaminant source.
The decontamination process adheres to fundamental principles such as speed, preventing dispersion, waste disposal, timeliness, and cost-effectiveness. The faster decontamination is performed, the higher its effectiveness. Treating contaminants by wetting them prevents their dispersion into the air. Common decontamination methods include: – Removing at least 8mm of contaminated surface material from objects – Washing clothing in dedicated washing machines – Washing hands, feet, or skin with neutral detergent 3-4 times within 2 minutes, or using a titanium oxide paste wash.

Post-Exposure Management and Recovery

If exposure is suspected even after decontamination procedures, seeking medical professional assistance is best. To minimize exposure damage and aid recovery, measures to prevent internal absorption and adequate nutritional support are necessary. Most exposures heal naturally within days, requiring continuous monitoring and follow-up measures throughout this process.

Conclusion

Radiation protection is a critical task for safeguarding life from the dangers of radiation. Accurate understanding of radiation and effective shielding reduce unnecessary fear and provide the foundation for safely utilizing radiation’s benefits when necessary. As technology advances, radiation protection standards and methods continue to strengthen, and research and practices to enhance the safety of radiation use will persist into the future.