Introduction
Health physics aims at safeguarding the population from the damaging consequences of ionizing radiation whilst permitting the advantageous use of this radiation in a number of fields such as science, industry and medicine. The discovery of information on consequences of ionizing radiation on biological systems and risk of exposure necessitate the establishment of radiation protection measures. The original limits aimed at preventing obvious effects of exposure such as skin cancer. However, with the increase in knowledge on the effects of radiation these interventions have shifted to averting the delayed outcomes of radiation such as cancer. The general method in the evolution of protection standards depends on risk approximations with minimal likelihood of miscalculating the effects of radiation exposure. Since the majority of observed radiation effects happen at elevated dosages and dose rates, the information obtained from affected populations is reduced to low doses. This enables the approximation of hazards that happen in occupational surroundings.
The creation, transport, consumption, and circulation of electricity produce power frequency electromagnetic fields (EMF) (Stam 1). The alternating current and the resultant electromagnetic field (EMF) is 50 hertz in Europe, Africa, Asia, Australia and South America (Stam 1). The remaining parts of the world have an EMF frequency of 60 hertz. Facilities such as radar equipment, microwave ovens, specified medical applications, mobile communication systems, and broadcasting transmitters spawn radiofrequency EMF (Stam 1). As much as radiation has immense use in technology and development, the health risks associated with exposure to radiation are lethal. Therefore, government agencies need to set rules that protect its citizens from the detrimental effects of radiation. This paper compares the radiation regulations between Europe and the United States. It pays attention to occupational and the public standard limits of exposure as well as the safety measures put in place in these two regions.
Regulatory Authorities in Radiation Protection
Regulations are constituents of independent secondary legislation and are exclusively implemented by members within a specified jurisdiction. Regulations are binding and need to be applied completely by the affected member states. The European Union, for example, covers several states in Europe and has a set of regulations concerning radiation protection. Some of the regulatory authorities on radiation protection in Europe are National Council on Radiation Protection (NRCP), Council of the European Union, and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) (Stam 1). The Heads of European Radiological protection Competent Authorities (HERCA) are other authorities that seek to establish and sustain a group of key radiation safety supervisory bodies in Europe.
The United States of America, on the other hand, has several radiation regulatory authorities such as EPA (Environmental Protection Agency), “the Department of Energy (DoE), the Nuclear Regulatory Commission (NRC), Department of Defense (DoD), the Department of Health and Human Services (DHHS), the Department of Labor (DoL), the Department of Transportation (DoT), and the Federal Emergency Management Agency (FEMA)” (“Radiation at EPA: The First 30 Years” 5). These authorities work together to restrict public and occupational exposure to radiation. EPA’s key objectives are to propagate appropriate standards that restrict the release of artificial radioactive substances to the surroundings and the creation of general radiation protection guidelines to be adhered to by state agencies in the advancement of their radiation strategies (“Radiation at EPA: The First 30 Years” 4).
Protraction Standard Limits
The protraction standard limits are established by the ICRP and endorsed by the US NCRP and are, therefore, similar in the U.S. and Europe. These bounds are 210 Bq/L in water for human consumption and a yearly work-related radiation dose threshold of 0.05 Sv.
Exposure of the General Public
Since Europe comprises several countries, the Council of the European Union has published two documents called ‘the Recommendation’ and ‘the Directive’ (Stam 1). The Recommendation contains the limits of exposure to the general public, whereas the directive contains the lower limits of health and safety requisite as regards the exposure of workers to the dangers of electromagnetic fields (EMF). The exposure limits in the Recommendation are 5000 V/m electric field strength, a magnetic flux density of 100 µT and corresponding field strength of 41 V/m for 50 Hz (ELF). For 900 MHz (GSM), the magnetic flux density is 0.14 µT with an equivalent plain wave power density of 4.5 W/m2 and electric field strength of 58 V/m (Stam 9). The 1800 MHz (GSM) has a magnetic flux density of 0.2 µT, plain wave power density of 9 W/m2 and electric field strength of 61 V/m. For 2100 MHz (UMTS), the magnetic flux density is also 0.2 µT and the plain wave power density is 10 W/m2 (Stam 9).
The limits of exposure in the Directive are 10,000 V/m electric field strength and magnetic flux density of 500 µT for 50 Hz (ELF). For 900 MHz (GSM), the electromagnetic fields strength is 90 V/m, magnetic flux density is 0.3 µT and has an equivalent plain wave power density of 22.5 W/m2. For 1800 MHz (GSM), the electric field strength is 127 V/m, magnetic flux density is 0.42 µT and equivalent plain wave power density is 45 W/m2. At 2100 MHz (UMTS), the electric field strength is 137 V/m, the magnetic flux density is 0.45 µT and the equivalent plain wave power density is 50 W/m2 (Stam 11). For the purposes of coherence and flow in this paper, the exposure limits and action plan values in the Directive and the Recommendation are as mentioned in this section.
The EMF policies in European member states are categorized into three main groups. In the first category, the Recommendation is incorporated into obligatory national legislation implying that the fundamental limits and reference quantities are mandatory. Countries in this group include “Czech Republic, Estonia, Greece, Hungary, Luxembourg, Portugal and Romania” (Stam 2). In Luxemburg, the creation of living quarters around overhead power lines is prohibited by law. The restricted area falls within a radius of twenty meters around power lines with a capacity of 60 kilovolts and thirty meters around lines whose capacity ranges from 100 to 220 kilovolts.
The second category of member states has lenient legislation since the general confines as set by the Recommendation are not compulsory. Some of the countries in this category have protective guidelines that electricity firms can obey out of their own volition. For example, Spain’s local authorities do not allow the erection of fresh power lines in proximity to public places, educational institutions and residential places. Other countries belonging to this group are Cyprus, Ireland, Denmark, Malta, Austria, and the United Kingdom among others.
Public demand and the precautionary tenet necessitate the implementation of stringent fundamental limitations and reference levels in the third category of member states. The reference levels of the Recommendation are used as the effective exposure limits and must not be surpassed. However, the specific rules vary from one state to another. In Belgium, for example, the reference value in the Recommendation is the national maximum value in the electric field intensity. In Bulgaria, the least distance between residential homes and power stations depends on the voltage. These are the only restrictions that apply apart from restrictions on video screen discharges, which is 0.5 percent of the values indicated in the guidelines (the Recommendation). There are immense similarities between the Italy’s magnetic flux density restrictions and the reference quantities.
There is no federal decree regarding public exposure to power frequency EMF in the U.S. However, a few states such as Colorado, Hawaii, Ohio, and Connecticut have implemented modifications of the ‘prudence avoidance’ tenet (Stam 4). This implies that community contact with electromagnetic force having a frequency of 60 hertz needs to be restricted. Therefore, other states have permanent thresholds for the electromagnetic power lines. These limits range from a fifth to double the reference level stipulated in the Recommendation. These states include New York, Montana, Florida, New Jersey, Minnesota, and Oregon (Stam 4).
In the regulation of radiofrequency electromagnetic waves, three categories also exist among the member states of the European Union, this time comprising different countries per category. The regulations in this area are categorized into countries where the Recommendation is the law, countries where the restriction limits as stipulated by the Recommendation are not binding, and countries with more stern regulatory measures because of public demand. In the U.S., the fundamental limits established by the national laws that govern radio transmitters resemble those in the Recommendation. However, the reference quantities are slightly higher than in Europe because they are computed using a different model. These basic limitations, in addition, are only applicable to moveable contrivances that are in proximity to the body. In immovable gadgets, the reference levels are the effective exposure limits.
Occupational Exposure
The last two decades have witnessed a tremendous increase in the global use of fluoroscopically guided interventional processes. There is no doubt that interventional radiology offers extensive benefits to patients in procedures such as computed tomography-guided processes and computed tomography fluoroscopy. However, these procedures emit “patient radiation doses high enough to cause radiation effects and occupational doses to interventional radiologists high enough to cause concern” (Miller et al. 608).
The level of exposure to radiation varies in dosage from one radiologist to another even when carrying out identical procedures at the same patient dose (Miller et al. 608). It is now known that cataracts of the eye arise at much lesser doses than was previously believed. In addition, there is no known upper limit dose for the development of cataracts though it is thought to be less than 0.1 Gy (Miller et al. 608). The time required to develop cataracts after exposure also decreases as the radiation dose increases. Therefore, it is essential to have established guidelines that limit occupational exposure to radiation to protect radiologists from the detrimental effects of radiation. Suitable protection gear and equipment also need to be present as well as protection measures that conform to local and international stipulations. These measures need to take into account the ergonomic damage attributable to personal protective strategies.
In Europe, the Directive permits member states to establish sterner exposure limits. In addition, the transposition deadline is delayed, and assortments of regulations are in use. Countries such as Italy, Lithuania, Slovakia, Romania, the Czech Republic, and Latvia use the Directive action and exposure limit values. Countries such as Estonia, Hungary and Germany among others do not have nationwide legislation with compulsory restrictions for EMF of 50 hertz in the workplaces. However, some of these countries have voluntary suggestions or values from specialized organizations, governments, or insurance firms, which are adopted by the health and safety inspectorate as safety precautions for acceptable regulation of EMF hazards. In Germany, for example, the restrictions established by specialized organizations are three times those indicated in the Directive. A separate category of countries has sterner rules with some countries adopting restriction limits that are approximately two and a half times those stipulated in the directive.
In the United States, the American College of General and Industrial Hygiene proposes higher limits than those present in the Directive (Stam 8). However, these suggestions cannot be implemented due to lack of national legislation. For the radiofrequency electromagnetic waves, the U.S. uses exposure limit values that are similar to those found in the Directive. However, the action values for electronic and EMF intensities are 17% greater than in the Directive because of differences in computational procedures. The safeguarding of military employees in NATO utilizes similar action and exposure limit values in its standardization agreement.
Conclusion
The findings of this paper are in agreement with some of the observations in a report by Hammitt et al. (1215), which suggests that the United States is more relaxed on radiation regulations than Europe. However, this is not to say that the U.S. lacks regulatory authorities on radiation protection. Therefore, the U.S. government needs to enforce these regulations as it is done in Europe. This move is likely to reduce the levels of occupational and the public exposure to radiation thereby curbing the hazards associated with radiation.
Works Cited
Hammitt, K. James, Jonathan B. Wiener, Brendon Swedlow, Denise Kall, and Zheng Zhou. “Precautionary Regulation in Europe and the United States: A Quantitative Comparison.” Risk Analysis. 25.5 (2005): 1215-1228. Web.
Miller, L. Donald, Eliseo Vañó, Gabriel Bartal, Stephen Balter, Robert Dixon, Renato Padovani, Beth Schueler, John F. Cardella, and Thierry de Baère. “Occupational Radiation Protection in Interventional Radiology: A Joint Guideline of the Cardiovascular and Interventional Radiology Society of Europe and the Society of Interventional Radiology.” J Vasc Interv Radiol. 21.5 (2010): 607–615. Web.
Radiation at EPA: The First 30 Years 2000. Web.
Stam, Rianne 2011. Comparison of International Policies on Electromagnetic Fields (Power Frequency and Radiofrequency Fields). Web.