## 2 Limits, Regulations, and Methods for the EMF (electromagnetic field) Assessment Process  
Starting on the 1 st of July 2016, all EU member states are required to implement Directive 2013/35/EU (also known as the EMF Directive) in their own national law, a directive that provides rules for the protection of persons against exposure to the electromagnetic field (EMF) [1]. As a result, all companies in the European Union are required to ensure that their employees are not exposed to electromagnetic radiation at levels higher than those defined by law. Some of these limits have just been defined in the new legislation. In Romania, the legislation includes the emergency ordinance GO (HG) 520 20/07/2016 regarding the minimum safety and health requirements regarding the exposure of workers to the risks generated by electromagnetic fields, as well as the order no. 1193/2006 regarding limiting the exposure of the general population to electromagnetic fields [6]. Thus, it is necessary to monitor and reduce the existing risk through preventive and corrective measures, where appropriate [7]. The main legislation on which the new European EMF Directive was based, is that issued by the ICNIRP (International Commission of Non-Ionizing Radiation Protection) [1]. The EMF Directive considers two biophysical categories of effects caused by ubiquitous electromagnetic fields:  
* thermal effects (range 100 kHz-300 GHz), such as the burning of skin tissues caused by energy absorption, which may occur upon exposure to high-frequency electromagnetic fields that may cause internal burns or blindness in extreme cases;
* non-thermal effects (range 1 Hz-10 MHz), such as muscle stimulation, nerves or various senses, caused by exposure to low-frequency electromagnetic fields (in some cases such situations can cause optical illusions, for example). Exposure Level Values (ELVs), which are based on the current intensity of the field inside the human body, are required to be respected for protection against any potential biophysical effect. However, they cannot be measured in practice, which is why Directive 2013/35/EU (also known as the EMF Directive) specifies the so-called action levels (AL--Action Levels) [8]. The safety of the human body placed in an electromagnetic field is thus ensured, according to law, if these levels are not exceeded. The thermal and non-thermal effects are dependent both on the intensity of the field but also on its frequency. For this reason, the directive defines frequency-dependent action levels in the range of 100 kHz-300 GHz. For this reason, the measuring equipment must correctly evaluate the intensity of the electromagnetic fields in relation to the frequency and consider the individual effects, such as in the vicinity of a radio transmitter [9]. The non-thermal effects are also dependent on the frequency of the signal that produces the electromagnetic field. Higher levels can affect human health in the long term, and corrective and protective actions are required. Low-frequency electromagnetic fields are usually present in the industrial environment and are usually pulsating fields. For this reason, the directive specifies the use of the WPM (Weighted Peak Method), which measures the peak values in the time domain as a reference method for non-sinusoidal wave fields. Measuring instruments already use this method, also called the shaped time domain (STD) method. This method is declared a reference method by the ICNIRP body, as well as by the EU Directive [1]. A new requirement of the EMF directive also specifies that the employer must develop a risk assessment method for each job. However, in most cases, such as in laboratories and offices where only low current devices are used, the declaration of conformity with the CE marking is sufficient. Of course, this principle is not applied in the case of HV equipment [10].