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Current international guidelines and limits for occupational and public (lower limits) exposure to electromagnetic fields (EMF) are set in order to ensure that the strengths of fields that humans experience are not harmful to health. At present, they are based on the current scientific knowledge on the prevention of acute effects. The guideline limits incorporate a large safety margin with respect to the thresholds of those effects, and therefore do not represent a precise delineation between safety and hazard. Normal exposure levels are in most cases much lower than the mentioned limits, preventing acute effects. The International Agency of Research on Cancer (IARC) has classified exposure to both extremely low frequency (ELF) magnetic field and to radiofrequency (RF) fields (at levels below limits for acute effects protection) as a class IIB, possibly carcinogenic to humans, and new animal studies have strengthened the demand for an update of this classification for RF fields. Concerns have been expressed about health and safety from occupational exposure to EMF at below the present guidelines, and a precautionary step might be advisable. Just as individuals can exercise Prudent Avoidance, government regulators, electric power companies and other companies where EMF exposure may occur, can also exercise prudence. In the following, we will give some examples of such measures.

The EU directive on exposure to electromagnetic fields was published in 2004, but due to some problems it was not introduced in the EU countries before 2016. However, still today, many companies are not aware of the legislation and have not taken measures to comply. This could perhaps be due to some of the practical problems they are facing in trying to comply. Here, we address some of these problems, such as showing compliance with the action levels for non-sinusoidal extremely low-frequency magnetic fields, time-averaging for the initial start-up current of handheld machines and time-averaging of radiofrequency fields when measuring plastic welding machines, including the uncertainty in the measurements. Finally, we discuss some of the problem concerning workers with special needs.

Concomitant fields are the unwanted transverse components that arise when spatial encoding gradients are applied in MRI. We measured the changing gradient magnetic field at multiple locations inside the scanner and examined the internal distribution and linearity of the three vector components of the field. Our results illustrate some not-so-obvious spatial characteristics of the gradient field, which can seem unintuitive at first glance, but are quite reasonable when considering electromagnetic theory and MRI-scanner physics constraints.

The designs of in vivo, in vitro and in silico studies do not adequately reflect the characteristics of long-term occupational EMF exposure; the higher exposure levels permitted for employees are nevertheless extrapolated on this basis. Epidemiological studies consider occupational exposure only in a very general way, if at all. There is a lack of detailed descriptive data on long-term occupational exposure over the duration of the working life. Most studies reflect exposure characteristics of the general population, exposures which are long-term, but at a comparably low level. Occupational exposure is often intermittent with high peak power followed by periods with no exposure. Furthermore, the EU EMF-Directive 2013/35/EU states a demand for occupational health surveillance, the outcome of which would be of great help to epidemiologists studying the health effects of EMF exposure. This paper thus aims to outline and specify differences between public and occupational exposure and to increase the understanding of specific aspects of occupational exposure which are important for long-term health considerations. This could lead to a future protection concept against possible hazards based on adequate descriptions of long-term exposures and also include supplementary descriptive features such as a “reset time” of biological systems and accurate dose quantities.

Performing work is associated with the impact on the worker’s body of many factors that can cause various adverse health effects. One example of this are the effects related to the simultaneous impact of electromagnetic and biomechanical factors, which occur while manually operating an electromagnetic field (EMF) sources. Minimising both the EMF influence and the musculoskeletal load (MSL) is not a simple issue; there are opposing practices in reducing them. The aim of this chapter is to analyse the realistically modelled influence of EMF on a worker in various postures and with respect to MSL. The main principles of modelling and evaluating the influence of EMF and MSL on humans, and ways of reducing them are discussed in this chapter. A high posture-related variability in the level of biophysical EMF influence (nine times) and MSL (five times) was shown, for example, in the operation of suspended welding guns. Torso bending and upper limb position showed the most significant influence on these factors. Such variability is considerably higher than the variability related to the range of biomechanical properties of the human body in the population and the contribution to the biophysical effects from EMF exposure caused by a non-sinusoidal pattern of EMF variability over time (also recognised as higher harmonics components in the waveform). However, the influence from the frequency pattern of EMF exposure may affect their evaluation above certain limits. It is advisable to first decrease the impact of electromagnetic factors by increasing the distance between the operator’s body and the EMF source, and then carry out a detailed evaluation counting the frequency composition (harmonics) in EMF exposure. Importantly, it must be remembered that increasing the distance between the operator and the welding gun usually increases the MSL, which needs to be compensated for by ensuring the relevant ergonomic support.

Workers in occupational settings are usually exposed to numerous sources of electromagnetic fields (EMF) and to different physical agents. Risk assessment for industrial workplaces concerning EMF is not only relevant to operators of devices or machinery emitting EMF, but also to support-workers, bystanders, service and maintenance personnel, and even visitors. Radiofrequency EMF guidelines published in 2020 by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) may also be indirectly applied to assess risks emerging from EMF sources at workplaces by technical standards or legislation. To review the applicability and adequacy to assess exposure to EMF in occupational settings in the European Union, the most current ICNIRP guidelines on radiofrequency EMF are reviewed. Relevant ICNIRP fundamentals and principles are introduced, followed by practical aspects of exposure assessment. To conclude, open questions are formulated pointing out gaps between the guidelines' principles and occupational practice, such as the impact of hot and humid environments and physical activity or controversies around ICNIRPS's reduction factors in view of assessment uncertainty in general. Thus, the article aims to provide scientific policy advisors, labor inspectors, or experts developing standards with a profound understanding about ICNIRP guidelines' applicability to assess hazards related to radiofrequency EMF in occupational settings.

Several in vitro and in vivo studies have investigated if a magnetic resonance imaging (MRI) examination can cause DNA damage in human blood cells. However, the electromagnetic field (EMF) exposure that the cells received in the MR scanner was not sufficiently described. The first studies looking into this could be regarded as hypothesis-generating studies. However, for further exploration into the role of MRI exposure on DNA integrity, the exposure itself cannot be ignored. The lack of sufficient method descriptions makes the early experiments difficult, if not impossible, to repeat. The golden rule in all experimental work is that a study should be repeatable by someone with the right knowledge and equipment, and this is simply not the case with many of the recent studies on MRI and genotoxicity. Here we discuss what is lacking in previous studies, and how we think the next generation of in vitro and in vivo studies on MRI and genotoxicity should be performed. Bioelectromagnetics.

Studies on sleep after exposure to radiofrequency electromagnetic fields have shown mixed results. We investigated the effects of double-blind radiofrequency exposure to 1,930-1,990 MHz, UMTS 3G signalling standard, time-averaged 10 g specific absorption rate of 1.6 W kg(-1) on self-evaluated sleepiness and objective electroencephalogram architecture during sleep. Eighteen subjects aged 18-19 years underwent 3.0 hr of controlled exposure on two consecutive days 19:45-23:00 hours (including 15-min break); active or sham prior to sleep, followed by full-night 7.5 hr polysomnographic recordings in a sleep laboratory. In a cross-over design, the procedure was repeated a week later with the second condition. The results for sleep electroencephalogram architecture showed no change after radiofrequency exposure in sleep stages compared with sham, but power spectrum analyses showed a reduction of activity within the slow spindle range (11.0-12.75 Hz). No differences were found for self-evaluated health symptoms, performance on the Stroop colour word test during exposure or for sleep quality. These results confirm previous findings that radiofrequency post-exposure in the evening has very little influence on electroencephalogram architecture but possible on spindle range activity.