Icnirp Guidelines for Limiting Exposure to Electromagnetic Fields (100 Khz to 300 Ghz)

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Icnirp Guidelines for Limiting Exposure to Electromagnetic Fields (100 Khz to 300 Ghz) INTERNATIONAL COMMISSION ON NON-IONIZING RADIATION PROTECTION ICNIRP GUIDELINES FOR LIMITING EXPOSURE TO ELECTROMAGNETIC FIELDS (100 KHZ TO 300 GHZ) PUBLISHED IN: HEALTH PHYS 118(5): 483–524; 2020 PUBLISHED AHEAD OF PRINT IN MARCH 2020: HEALTH PHYS 118(00):000–000; 2020 ICNIRP PUBLICATION – 2020 Special Submission GUIDELINES FOR LIMITING EXPOSURE TO ELECTROMAGNETIC FIELDS (100 kHz to 300 GHz) International Commission on Non-Ionizing Radiation Protection (ICNIRP)1 recognized that there may be limitations to this knowledge that Abstract—Radiofrequency electromagnetic fields (EMFs) are used to enable a number of modern devices, including mobile telecom- could have implications for the exposure restrictions. Accord- munications infrastructure and phones, Wi-Fi, and Bluetooth. As ingly, the guidelines will be periodically revised and updated as radiofrequency EMFs at sufficiently high power levels can ad- advances are made in the relevant scientific knowledge. The versely affect health, ICNIRP published Guidelines in 1998 for hu- present document describes the guidelines and their ratio- manexposuretotime-varyingEMFsupto300GHz,which included the radiofrequency EMF spectrum. Since that time, there nale, with Appendix A providing further detail concerning has been a considerable body of science further addressing the re- the relevant dosimetry and Appendix B providing further lation between radiofrequency EMFs and adverse health outcomes, detail regarding the biological and health effects reported as well as significant developments in the technologies that use ra- in the literature. diofrequency EMFs. Accordingly, ICNIRP has updated the radio- frequency EMF part of the 1998 Guidelines. This document presents these revised Guidelines, which provide protection for humans from exposure to EMFs from 100 kHz to 300 GHz. PURPOSE AND SCOPE Health Phys. 118(5):483–524; 2020 The main objective of this publication is to establish guidelines for limiting exposure to EMFs that will provide INTRODUCTION a high level of protection for all people against substantiated THE GUIDELINES described here are for the protection of adverse health effects from exposures to both short- and humans exposed to radiofrequency electromagnetic fields long-term, continuous and discontinuous radiofrequency (EMFs) in the range 100 kHz to 300 GHz (hereafter “radiofre- EMFs. However, some exposure scenarios are defined as quency”). This publication replaces the 100 kHz to 300 GHz outside the scope of these guidelines. Medical procedures part of the ICNIRP (1998) radiofrequency guidelines, as may utilize EMFs, and metallic implants may alter or per- well as the 100 kHz to 10 MHz part of the ICNIRP turb EMFs in the body, which in turn can affect the body (2010) low-frequency guidelines. Although these guidelines both directly (via direct interaction between field and tissue) are based on the best science currently available, it is and indirectly (via an intermediate conducting object). For example, radiofrequency ablation and hyperthermia are both used as medical treatments, and radiofrequency EMFs 1ICNIRP, c/o BfS, Ingolstaedter Landstr. 1, 85764, Oberschleissheim, can indirectly cause harm by unintentionally interfering Germany; with active implantable medical devices (see ISO 2012) or The International Commission on Non-Ionizing Radiation Protection altering EMFs due to the presence of conductive implants. (ICNIRP) collaborators are listed in the Acknowledgement section. ICNIRP declares no conflict of interest. As medical procedures rely on medical expertise to weigh po- For correspondence contact: Gunde Ziegelberger, c/o BfS, tential harm against intended benefits, ICNIRP considers Ingolstaedter Landstr. 1, 85764 Oberschleissheim, Germany, or such exposure managed by qualified medical practitioners email at [email protected]. (Manuscript accepted 3 September 2019) (i.e., to patients, carers and comforters, including, where rele- 0017-9078/20/0 vant, fetuses), as well as the utilization of conducting materials Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Health Physics Society. This is an open-access for medical procedures, as beyond the scope of these guide- article distributed under the terms of the Creative Commons Attribution- lines (for further information, see UNEP/WHO/IRPA 1993). Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it Similarly, volunteer research participants are deemed to be is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without outside the scope of these guidelines, providing that an insti- permission from the journal. tutional ethics committee approves such participation follow- DOI: 10.1097/HP.0000000000001210 ing consideration of potential harms and benefits. However, www.health-physics.com 483 484 Health Physics May 2020, Volume 118, Number 5 occupationally exposed individuals in both the clinical exposure situations and populations. Where no such and research scenarios are defined as within the scope threshold could be explicitly obtained from the radiofre- of these guidelines. Cosmetic procedures may also utilize quency health literature, or where evidence that is inde- radiofrequency EMFs. ICNIRP considers people exposed pendent from the radiofrequency health literature has to radiofrequency EMFs as a result of cosmetic treat- (indirectly) shown that harm could occur at levels lower ments without control by a qualified medical practitioner than the “EMF-derived threshold,” ICNIRP set an “oper- to be subject to these guidelines; any decisions concern- ational threshold.” These are based on additional knowl- ing potential exemptions are the role of national regula- edge of the relation between the primary effect of tory bodies. Radiofrequency EMFs may also interfere exposure (e.g., heating) and health effect (e.g., pain), with electrical equipment more generally (i.e., not only to provide an operational level with which to derive re- implantable medical equipment), which can affect health striction values in order to attain an appropriate level indirectly by causing equipment to malfunction. This is of protection. Consistent with previous guidelines from referred to as electromagnetic compatibility, and is out- ICNIRP,reduction factors were then applied to the resul- side the scope of these guidelines (for further informa- tant thresholds (or operational thresholds) to provide ex- tion, see IEC 2014). posure restriction values. Reduction factors account for biological variability in the population (e.g., age, sex), variation in baseline conditions (e.g., tissue tempera- PRINCIPLES FOR LIMITING ture), variation in environmental factors (e.g., air tem- RADIOFREQUENCY EXPOSURE perature, humidity, clothing), dosimetric uncertainty These guidelines specify quantitative EMF levels for associated with deriving exposure values, uncertainty personal exposure. Adherence to these levels is intended associated with the health science, and as a conservative to protect people from all substantiated harmful effects of measure more generally. “ radiofrequency EMF exposure. To determine these levels, These exposure restriction values are referred to as ba- ” ICNIRP first identified published scientific literature sic restrictions. They relate to physical quantities that are concerning effects of radiofrequency EMF exposure on closely related to radiofrequency-induced adverse health ef- biological systems, and established which of these were fects. Some of these are physical quantities inside an exposed both harmful to human health3 and scientifically substan- body, which cannot be easily measured, so quantities that are “ ” tiated. This latter point is important because ICNIRP con- more easily evaluated, termed reference levels, have been siders that, in general, reported adverse effects of derived from the basic restrictions to provide a more-practical radiofrequency EMFs on health need to be independently means of demonstrating compliance with the guidelines. Ref- verified, be of sufficient scientific quality and consistent erence levels have been derived to provide an equivalent de- with current scientific understanding, in order to be taken gree of protection to the basic restrictions, and thus an as “evidence” and used for setting exposure restrictions. exposure is taken to be compliant with the guidelines if it Within the guidelines, “evidence” will be used within this is shown to be below either the relevant basic restrictions context, and “substantiated effect” used to describe re- or relevant reference levels. Note that the relative concor- ported effects that satisfy this definition of evidence. dance between exposures resulting from basic restrictions The reliance on such evidence in determining adverse and reference levels may vary depending on a range of fac- health effects is to ensure that the exposure restrictions tors. As a conservative step, reference levels have been are based on genuine effects, rather than unsupported derived such that under worst-case exposure conditions claims. However, these requirements may be relaxed if (which are highly unlikely to occur in practice) they will there is sufficient additional knowledge (such as under- result in similar exposures to those specified by the ba- standing of the relevant biological interaction mecha- sic restrictions. It follows that in the vast majority of nism) to confirm that adverse health effects are reasonably cases, observing the
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