A college report on the present status of medical care insurance and allied problems.

Chapter 24 - Radiation and oxidative stress

Academic program recommendations for graduate degrees in medical physics: AAPM Report No. 365 (Revision of Report No. 197).

Purpose: The purpose of this study is to evaluate the global scientific publication of biological research of low dose radiation for the past 30 years and provide the insights into the characteristics of research activities and major topics regarding biological effects of low dose radiation exposure.Materials and methods: We bibliometrically investigated the biological research publication of radiation exposure less than 100 mSv. References published from 1987 to 2016 were achieved from the Scopus database and filtered by several criteria such as publication types, research fields, and radiation dose range.Results: Total 753 references were assembled for the bibliometric analysis on the biological studies of radiation effect less than 100 mSv. It provided fundamental knowledge of research, including production tendency, contribution, impact journals, and major research themes. Based on the keyword analysis, we found that specific topics on the biological response to radiation exposure have been changed from the examination of low dose radiation-induced phenomena to the investigation of how to induce a physiological response. In addition, featured articles showed the various views on the biological effects of radiation less than 100 mSv in 30 years publication, depending on radiation doses and types.Conclusions: Continuous studies in large programs of low dose radiation led to the increment of research achievements in accordance with societal needs in radiation safety regulation for health protection. Our findings can surely help radiation researchers to gain insights and penetration in low dose risk research for radiation protection, and establish a further research direction.

Numerous developments have occurred in commercial space tourism since a feature article in Space Weather first addressed the growing interest in this facet of human space flight [Turner, 2007]. For example, in July 2012, at the Farnborough International Air Show, Virgin Galactic announced that SpaceShipTwo is on the verge of the first commercial space tourism suborbital flight (Virgin Galactic press release, 10 July 2012, available at http://www.virgingalactic.com/news/item/xxx/): Virgin Galactic Founder Sir Richard Branson revealed that the company has now accepted deposits for suborbital flights on SpaceShipTwo from 529 future astronauts, a number greater than the total count of people who have been to space throughout human history. This news comes following a flurry of recent test activity and confirmation that all major components of SpaceShipTwo's rocket system have been qualified for powered flight, on track to begin before the year's end. In addition, progress is being made toward operating the first commercial orbital space tourism flights. Bigelow Aerospace launched and still monitors the flights of two subscale inflatable modules, Genesis I (launched 12 July 2006) and Genesis II (launched 28 June 2007), and continues to develop its BA 330 orbital habitation module (Bigelow Aerospace home page, 3 October 2012, available at http://www.bigelowaerospace.com/index.php). Meanwhile, on 31 May 2012 and again on 10 October 2012, SpaceX successfully demonstrated its ability to deliver a commercial resupply module, the Dragon, to the International Space Station via its own launch vehicle, the Falcon 9. The Dragon allows for both cargo and crew variants (SpaceX Dragon Capsule, 11 October 2012, available at http://www.spacex.com/dragon.php): To ensure a rapid transition from cargo to crew capability, the cargo and crew configurations of Dragon are almost identical, with the exception of the crew escape system, the life support system and onboard controls that allow the crew to take over control from the flight computer when needed. This focus on commonality minimizes the design effort and simplifies the human rating process, allowing systems critical to Dragon crew safety and space station safety to be fully tested on unmanned demonstration flights and cargo resupply missions. Also in May 2012, Bigelow and SpaceX announced that they would begin working together on a joint effort to provide a fully commercial launch-to-orbit-to-reentry orbital space experience (Bigelow Aerospace and SpaceX joint venture, available at http://www.spacex.com/press.php?page=20120510): Space Exploration Technologies (SpaceX) and Bigelow Aerospace (BA) have agreed to conduct a joint marketing effort focused on international customers. The two companies will offer rides on SpaceX's Dragon spacecraft, using the Falcon launch vehicle to carry passengers to Bigelow habitats orbiting the Earth. Thus, the conclusion of the 2007 Space Weather journal article remains valid today, with a growing sense of urgency [Turner, 2007]: As society itself expands into the frontiers of space, the space weather community must be prepared to welcome increasing roles and responsibilities to ensure the safety of these intrepid pioneers. A 2008 report prepared for the Federal Aviation Administration (FAA) Office of Commercial Space Transportation summarized space weather impacts on suborbital space flight [Turner et al., 2008]. Among its conclusions were that under typical conditions the radiation exposure to crew and passengers on a suborbital flight is less than that of a long-duration airline flight. Although the radiation risk for crew and passengers is minimal except possibly at high latitudes and during solar and geomagnetic disturbances, crew and passengers should be briefed on the radiation risks in the spirit of informed consent, and they should be monitored during the mission for radiation exposure. This means that the providers of suborbital flights will require, as part of their support staff, experts familiar with the space environment (space weather), techniques for monitoring the radiation environment, techniques and models for estimating the doses with the body under realistic shielding, and the biological effects of radiation in order to ensure crew and passenger well being. The transition to commercial orbital space flight will substantially increase participants’ exposure to radiation and will lead to increased demands for space weather expertise. Even during a nominal space environment (400 kilometers altitude, with orbit inclination less than 30 degrees) under reasonable shielding, a week's exposure will be on the order of 100 cross-country airplane flights, or close to the typical U.S. resident's annual exposure [Turner, 2012]. This exposure could increase significantly if the mission altitude or inclination is increased or if there is a solar storm. Here we address the biological effects of radiation exposure, the radiation exposure of suborbital and orbital flights, and the role of the space weather community in commercial space flight. The biological impacts of exposure to the unique space radiation environment are discussed in Turner [2007, and references therein]. Recent reports that discuss the details of space radiation exposure include National Research Council [2012], Cucinotta et al. [2010, 2011], and Durante and Cucinotta [2011]. The key points are summarized here. The general U.S. population's annual exposure to radiation is less than 0.5 cSv per year [National Council on Radiation Protection and Measurements, 2009]. Exposure from a typical midlatitude cross-country air flight is about 25 ?Sv. Limits for radiation workers are generally less than 5 cSv per year. The cumulative experience of U.S. astronauts has ranged from 0.1 to 10 cSv. The exposure rate varies with altitude, inclination, solar cycle, solar activity, vehicle shielding, vehicle orientation, and location within the vehicle. Mission-averaged rates have ranged from 0.01 to 0.4 cSv per day. A high dose of radiation over a short period can lead to acute effects such as headaches, nausea, and skin “burns.” In extreme cases, the effects of high dose rates can be severe, either directly through radiation sickness or indirectly, as from vomiting in a space suit. Acute effects generally do not manifest at exposures below 0.7 Gy-Eq attained within a few hours. In 2010, NASA developed an acute effects projection model combining radiation transport codes and a probabilistic model of acute radiation risk (ARRBOD) [Kim et al., 2010]. Table 1 shows the scale of effects and threshold doses in gray equivalent to induce the indicated response within 24 hours, with no medical intervention, according to that model. To date, astronaut exposures have not approached even the lowest acute exposure thresholds. A lower dose over a prolonged period can have long-term impacts, including increased risk of cancer, effects on genetics or fertility, development of cataracts, and cumulative damage to tissue (particularly the central nervous system, digestive system, cardiovascular system, and immunological system). A good general rule, if used with caution and applied only to doses above a few mSv, has held that a 20 cSv (equivalent dose) exposure increases the probability of a fatal cancer by 1 percent [National Council on Radiation Protection and Measurements, 1993]. In 2012, NASA increased funding for studies on these “noncancer” effects, particularly impacts on the central nervous system (NASA Space Radiation Element of the Human Research Program, 2012, available at http://www.nasa.gov/centers/johnson/slsd/about/divisions/hacd/hrp/space-radiation.html). The effects of radiation on occupants of future commercial space vehicles may vary with the occupant's role in the mission. Typical passengers may be the least affected if they experience only one mission lasting tens of minutes (suborbital) or on the order of a week (orbital). However, there are cases where radiation exposure poses an elevated risk. For example, the National Council on Radiation Protection and Measurements recommends that pregnant females not fly in space, noting that [National Council on Radiation Protection and Measurements, 2000, p. 145] “The special radiation risks for the embryo/fetus are malformation and mental retardation…” In addition, crew members, who may fly many suborbital flights in a single month or may spend significant time in an orbiting space station, will face a correspondingly larger risk. Although not the focus of this article, radiation also poses a risk to spacecraft systems. Risks include a threat to avionics if a vehicle is launched during periods of enhanced energetic radiation, single-event effects to electronics in orbit, and spacecraft charging effects [Turner et al., 2008]. It was reported that 5 months after its launch, Genesis I (a prototype of the Bigelow Aerospace inflatable habitation module) suffered an anomaly during a solar storm that could have led to the end of the mission [David, 2007]. A study for the FAA Office of Commercial Space Flight [Turner et al., 2008] looked at both biological and systems impacts of the radiation environment on commercial suborbital space flight. The study examined four different suborbital trajectories at three different launch latitudes. The estimated participant doses from background radiation during solar minimum (galactic cosmic radiation maximum) are summarized in Table 2. The study also examined the impact of solar radiation events. A key conclusion was that for launch latitudes within 45 degrees of the equator, the solar storm impacts were less than the background cosmic radiation (Figure 1). The same report examined the risk of impact to vehicle avionics and concluded that with reasonable attention to component selection and good space system design practices, the risk was negligible during nominal radiation conditions. However, it would be prudent to avoid launch during a solar particle event or during disturbed geomagnetic conditions. Likely delay times to wait for more favorable launch conditions would be on the order of a day and only rarely more than a few days. Virgin Galactic suborbital flights will launch from SpacePort America, near Truth or Consequences, N. M. Located at approximately 33 degrees north latitude, the trajectory, reaching an altitude just over 100 kilometers, will be well within the protection of the Earth's magnetosphere, significantly reducing the radiation threat from solar particle events to both passengers and avionics. Compared to suborbital flights, the advent of commercial orbital space flight will significantly increase the radiation risk to passengers and avionics. The radiation exposure will depend on mission duration, orbital altitude, inclination, shielding, and details of the dynamic space environment. Figure 2 shows how the effective dose will vary with altitude and inclination under nominal 10 grams per square centimeter shielding during solar minimum conditions [Turner, 2012]. The impact of a solar storm is harder to quantify because it depends not only on the strength of the solar particle event and the altitude and inclination of the orbit but also on the relative timing of the peak of the event and the vehicle's possible transit of high-latitude regions above the geomagnetic cutoff for high-energy protons in the magnetosphere. For sufficiently low inclination (less than 30 degrees) or for sufficiently advantageous orbit phasing, the exposure can actually go down due to the effects of a “ Forbush decrease” in the galactic cosmic rays during a significant coronal mass ejection (http://science.nasa.gov/science-news/science-at-nasa/2005/07oct_afraid/, 7 October 2005). However, for sufficiently high inclination (above 50 degrees) and particularly unfortunate phasing, the effective dose could be 10-20 percent of the deep space exposure, or as much as a few tens of mSv. While it would be prudent to delay launch if a solar storm is in progress or deemed to be impending, a mission already under way has very little flexibility in its response to a storm. The crew and passengers could be restricted to a more shielded portion of the vehicle, reconfigurable shielding could be deployed, or the vehicle could return to Earth once orbital conditions for a favorable reentry exist. The choice of orbital altitude and inclination will likely be driven not by radiation risk considerations but by more immediate engineering and commercial considerations. Higher inclinations cover more of the Earth's population, and space tourists may desire to “see their house from orbit.” Providers may also want to go to high inclination to offer wider Earth coverage to the research community (for a fee). However, higher inclinations come at a mass performance penalty to the launch vehicles. Bigelow Aerospace has not published a destination altitude or inclination for its BA 330 module. However, its prototype vehicles Genesis I (http://nssdc.gsfc.nasa.gov/nmc/spacecraftOrbit.do?id=2006-029A) and Genesis II (http://nssdc.gsfc.nasa.gov/nmc/spacecraftOrbit.do?id=2007-028A) both have an orbit inclination of 64.5 degrees with an altitude between 500 and 600 kilometers (300 and 365 miles). Both prototypes were launched by Russian rockets from near 51 degrees north latitude. If SpaceX is the launch provider for BA 330, it would launch from Kennedy Space Center (28.5 degrees north latitude). The radiation exposure will also depend on vehicle shielding. According to Bigelow Aerospace (home page, 3 October 2012, available at http://www.bigelowaerospace.com/index.php), “Bigelow Aerospace's shielding is equivalent to or better than the International Space Station and substantially reduces the dangerous impact of secondary radiation.” So what does this mean to the space weather community? Most significantly, opportunities will arise for small enterprises to provide the necessary consulting support. There will be a need to provide the participants with an understanding of the space environment and the effects of radiation. This will contribute to “informed consent” documents prior to flight. It will be prudent for providers to monitor the radiation exposure in the vehicle and to personalize information to the participants. Thus, there will be a need for simple, efficient, and effective dosimeters as well as improved simulation tools to estimate the radiation environment in the vehicle. Commercial flight operators will need tailored space situation awareness, so there will be a need for targeted space weather forecasts and nowcasts, leading to an expanding market for “Accu-Space-Weather” firms. Most importantly, these are not “someday” opportunities: with the emerging space tourism market, suborbital and orbital, these are opportunities that need to be filled today. Definitions of units are from the National Council on Radiation Protection and Measurements composite glossary (available at http://www.ncrponline.org/PDFs/NCRP%20Composite%20Glossary.pdf http://www.ncrponline.org/PDFs/NCRP%20Composite%20Glossary.pdf, updated July 2011). Effective dose (E): The sum over specified tissues of the products of the equivalent dose in a tissue (HT) and the tissue weighting factor for that tissue or organ (wT) (i.e., E = ?T wTHT). Effective dose (E) applies only to stochastic effects. The unit is the joule per kilogram (J kg-1) with the special name sievert (Sv). Equivalent dose: The mean absorbed dose (gray) in a tissue or organ modified by the radiation weighting factor for the type and energy of radiation incident on the body. The SI unit of equivalent dose is J kg-1 with the special name sievert (Sv); 1 Sv = 1 J kg-1. For low linear energy transfer radiations (e.g., gamma rays and electrons), the radiation weighting factor is assigned a value of unity; therefore, 1 Gy is numerically equivalent to 1 Sv. Gray (Gy): The SI unit of absorbed dose of radiation; 1 Gy = 1 J kg-1. Gray equivalent (Gy-Eq): The special name for the unit of the quantity gray equivalent (GT). Also given as the product of DT and Ri, where DT is the mean absorbed dose in an organ or tissue and Ri is a recommended value for RBE for deterministic effects for a given particle type i (i.e., GT = Ri × DT). An Ri value applies to the particle type incident on, or emitted from radioactivity within, the body. The dose limits for deterministic effects from space radiation are given in terms of the quantity gray equivalent. Sievert (Sv): The special name for the SI unit of dose equivalent, equivalent dose, and effective dose. 1 Sv = 1 J kg-1. J kg-1 is also the SI unit for the International Committee on Radiation Units and Measurements operational quantities. Ronald Turner is a fellow at Analytic Services Inc., Suite 800, 2900 South Quincy Street, Arlington, Va 22206. E-mail: ron.turner@anser.org mailto:ron.turner@anser.org

Society of Interventional Radiology Position Statement on Radiation Safety

Ionizing radiation safety in the medical field, referred to as radiation safety, is an action taken to protect patients, workers, community members, and the environment from the dangers of radiation. One of the efforts to achieve this is by increasing the qualifications of radiation workers in understanding and implementing radiation protection and safety through ionizing radiation safety and security training initiated by the Radiation Protection Officer (PPR) team at Dr. RSUP. Kariadi Semarang. During the current pandemic, implemented the training by modifying what was previously done using face-to-face and field practice into online delivery of material and making videos as a substitute for field practice. As a result, these activities can run well and smoothly. The impression from the training participants stated that this training was beneficial and should be done regularly. Keywords: training, ionizing radiation, radiation protection officer

Quantities and units which are commonly used in radiation protection are introduced. As the effects of radiation on the biological system forms the basis for radiation protection, the biological effects of radiation are briefly described. Radiation dose may be received by external exposure and internal exposure to radiation. The most important considerations of radiation protection consist of justification of practice, optimization of protection and dose limitation. Radiation dose may be received in three types of exposure situations, viz., planned, emergency and existing exposure situations. In nuclear facilities safe work practices are adopted and area monitoring and individual monitoring are performed. The tools for external exposure control, namely, time, distance and shielding need to be judiciously adopted as also the methods for controlling internal exposure.

The purpose of this study was to survey health service workers regarding their radiation safety knowledge and practice. Participants were health service workers (n = 721) who received an anonymous online survey by email to test their radiation safety knowledge. A knowledge test of 15 questions was completed by 412 respondents. The overall average percent correct was 77.9%. Health physicists/medical physicists had the highest average percent score (93.5%), while physician assistants scored the lowest (60.0%). Of all the respondents, only 64.0% reported they participated in periodic radiation safety training at their place of employment. The most common topic selected where participants wanted additional training was in biological effects of radiation (41.0%). In conclusion, radiation safety training and education needs to be developed and planned effectively. Areas or specialties with poor radiation safety knowledge need to be addressed with corresponding safety measures.

The unregulated use of radiation technology and isotopes in the initial days of their invention has led to many radiological incidents involving untoward exposure of radiation. There was a realization on harmful effects of radiation on living systems besides its benefits. Such effects prompted the scientific community to undertake systematic studies on biological effects of radiation which further lead to the bases of radiation protection. The studies not only comprised epidemiological but also many laboratory experiments with animal models and cellular systems. Such studies not only helped to protect radiation workers in particular but also helped the public and environment.These studies have led to better quantification and qualitative understandings and also an approach to understand mechanistic details of underlying mechanisms creating damage and their progression into complex response of life. The knowledge on risk has also helped to set limits and improve safe work practices. This chapter discusses basics of radiation biology, biological effects of radiation and their implications in radiation protection.

Objective: Long-term C-arm fluoroscopy exposes medical personnel to substantial radiation doses. Preventing this exposure requires protective equipment and radiation safety. This study examined anesthesia students' using fluoroscopy and preventive knowledge. Methods: This descriptive and cross-sectional study included 139 Vocational High School Anesthesia students. The "Healthcare Professional Knowledge of Radiation Protection" scale and a 13-question survey collected data. The scale was designed with a Likert scale and three sub-factors. If the total and sub-dimension item average score of the scale is below 5, it indicates that the level of knowledge of radiation protection among medical personnel is low, and if it is above 5, it indicates that the level of knowledge is high. Results: More than half of the students (59.8%) heard the radiation from the fluoroscopy device, the vast majority (82.7%) did not receive radiation protection training, 58.3% stayed away from the device while it was operating, and 70.5% stated that it is crucial to stay away from the device while it was operating. It was determined that there was a statistically significant difference (p<0.05) in the "Radiation Physics, Biology, and Radiation Usage Principles" sub-dimension of students who were male, in their second year of education, received radiation protection training, and offered reliable answers to a number of questions measuring their level of radiation knowledge. In addition, the research revealed a positive and highly significant correlation between the scale and its subdimensions. Conclusion: Although the scale scores of the students who received radiation protection training and had a high level of radiation knowledge were substantially higher than those of the other students, the average score of the students was less than 5. This indicates that students have an inadequate understanding of radiation protection. To prevent the negative biological effects of radiation on the human body, it is necessary to conduct epidemiological research, educate health care professionals and anesthesiology students about the effects and processes of this radiation on human cells, and provide frequent training. Radiation, radiation's biological effects, and radiation protection should be included in health students' curricula.

The development and proliferation of electronic devices that either intentionally or inadvertently emit nonionizing radiation have brought about immense interest in the subject. The promise of an increase in the number and use of such devices has concerned many persons who believe that the radiation hazards have not been sufficiently studied. Those who express concern about an inadequate understanding of the biological effects of nonionizing radiations point out that many electronic devices have already found their way into common use (e.g., microwave ovens, radar for pleasure boats, scanning lasers in supermarket checkout counters, near‐ultraviolet radiation in fluorescent lighting fixtures, and a variety of high‐intensity light sources). Other concerns include the many infrared, ultraviolet, microwave, and laser devices that might produce excessive occupational exposures. Because of the heightened public interest in electromagnetic radiation hazards, Congress enacted the Radiation Control for Health and Safety Act. The declared purpose of the act is to establish a national electronic product radiation control program, including the development and administration of performance standards to control the emission of electronic product radiation. The act covers both ionizing and nonionizing electromagnetic radiations emitted from any electronic product. This includes X‐rays and gamma rays and particulate, ultraviolet, visible, infrared, millimeter wave, microwave, radio‐frequency, and, interestingly enough, sonic, infrasonic, and ultrasonic radiation. Since the inception of the act, the federal government has conducted or funded research into the biological effects of radiation, with special emphasis on low‐level effects. Standards have been developed and promulgated for television set receivers, medical X‐rays (amendments to existing standard), cathode ray tubes, microwave ovens, and lasers. Calibration, measurement, and product testing laboratories have been established to ensure proper evaluation of accessible radiation from electronic products, and a compliance program has been developed to obtain manufacturers' adherence to established standards. During the course of standards development efforts, the Food and Drug Administration (FDA) has been required to consult with the Technical Electronic Product Radiation Safety Standards Committee (TEPRSSC), an advisory body established under the Act. Unlike some federal advisory committees, TEPRSSC has the authority to develop and recommend its own standards directly to the Secretary of Health and Human Services.Other federal agencies that are actively concerned with nonionizing radiation hazards include the Occupational Safety and Health Administration (OSHA), the Environmental Protection Agency (EPA), the National Institute for Occupational Safety and Health (NIOSH), and the National Institute of Environmental Health Sciences (NIEHS).

Although many pollutants of our civilization are new, radiation has been experienced by living organisms since their very beginning. Human activity—most significantly in medicine—has simply added to the dose. In a concise and lucid fashion, Hall explains the physics and the biologic effects of radiation, and its uses and dangers. Although written for the layperson, the book is also instructive for physicians, most of whom are unfamiliar with the radiation hazards faced by astronauts (and possibly by travelers on the Concorde), the indoor radon problem in energy-efficient homes, and the technique of positron emission tomography. The book is an antidote to the prevailing misinformation about the dangers of radiation. Hall continually emphasizes the need for perspective, ie, for balancing risks and benefits, and for comparing risks with the risks of practical alternatives (rather than with a utopian risk-free state). For example, Hall contrasts the relatively small public health problems resulting

A survey of the population of the Leningrad and Murmansk regions was conducted in 2016–2017. The survey was devoted to the study of preferred sources of information on radiation safety. The sample size in the Leningrad region was 962 respondents, and in the Murmansk region – 802 respondents. It was found that less than 30% of respondents living in the Leningrad and Murmansk regions show interest in obtaining information on radiation safety. The respondents noted the greatest importance in obtaining information on three topics: «the effect of radiation on the body and the impact on health», «radiation protection measures available at the place of residence», and «dangerous and safe radiation levels». The possibility of obtaining accessible and regular information about the radiation situation in the place of residence is in demand among approximately 45% of respondents in the Leningrad region and 37% in the Murmansk region. Television, Internet and the SMS alerts were most often chosen by respondents as the most appropriate source of such information. With age, the proportion of users of traditional media, especially television, is increasing, among women slightly more than among men. The population revealed distrust of the media as sources of information about the radiation situation and safety, the confidence index for all types of media is negative. In the Murmansk region, the index of confidence in the media is lower than that in the Leningrad region. Among all types of mass media, TV has the greatest confidence in the population. On the Internet, the official websites of Rospotrebnadzor and Rosatom, as well as the official websites of local authorities in the Leningrad region, which have positive trust index, have the greatest confidence in the population. Search services, blogs, social networks, media sites, and official sites of local authorities in the Murmansk region have negative confidence index. More than a half of the population considers the inclusion of special training programs in the system of secondary and higher education to be the most effective method of improving environmental literacy. The following methods of educational work are also in demand: lectures and seminars with the participation of specialists and watching videos.

Book Review: Biological Effects of Non-Ionizing Radiations: Cellular Properties and Interactions Biological Effects of Non-Ionizing Radiations: Cellular Properties and Interactions.SchwanHerman P.50 pp.TaylorLauriston S.Lectures in Radiation Protection and Measurements. National Council on Radiation Protection and Measurements, Publishers. Bethesda, Maryland.1987, $12.00 U.S.

This study provides a comprehensive overview of the principles of radiation protection and radiobiology. It defines and classifies radiation, distinguishing between ionizing and non-ionizing radiation. The biological effects of radiation, with a particular emphasis on its impact on DNA and cellular structures, are examined in detail. The text specifies radiation-sensitive and radiation-resistant tissues and explains both deterministic and stochastic effects. Additionally, the discussion encompasses radioepidemiological information and the relationship between linear energy transfer and DNA damage. The article delineates the classification of radiation areas as either controlled or supervised. It offers an extensive overview of the safety and protection methods employed in radiation work, including the ALARA (As Low As Reasonably Achievable) principle, the use of personal protective equipment, and dosimeters. Furthermore, it explains the radiation protection methods utilized in radiology units and outlines the precautions that should be taken during pregnancy. The article also presents recommendations for reducing radiation exposure. Overall, this article serves as a valuable resource on radiation safety for radiation workers and the public, containing essential information on protection from the harmful effects of radiation and safe working practices.