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NON-THERMAL EFFECTS EXPOSURE LIMIT VALUES AND ACTION LEVELS IN THE FREQUENCY RANGE FROM 0 Hz TO 10 MHz A. EXPOSURE LIMIT VALUES (ELVs) ELVs below 1 Hz (Table A1) are limits for static magnetic field which is not affected by the tissue of the body. ELVs for frequencies from 1 Hz to 10 MHz (Table A2) are limits for electric fields induced in the body from exposure to time-varying electric and magnetic fields. ELVs for external magnetic flux density from 0 to 1 Hz The sensory effects ELV is the ELV for normal working conditions (Table A1) and is related to vertigo and other physiological effects related to disturbance of the human balance organ resulting mainly from moving in a static magnetic field The health effects ELV for controlled working conditions (Table A1) is applicable on a temporary basis during the shift when justified by the practice or process, provided that preventive measures, such as controlling movements and providing information to workers, have been adopted. Table A1 ELVs for external magnetic flux density (B0) from 0 to 1 Hz Sensory effects ELVs Normal working conditions 2 T Localised limbs exposure 8 T Health effects ELVs Controlled working conditions 8 T

Health effects ELVs for internal electric field strength from 1 Hz to 10 MHz Health effects ELVs (Table A2) are related to electric stimulation of all peripheral and central nervous system tissues in the body, including the head. Table A2 Health effects ELVs for internal electric field strength from 1 Hz to 10 MHz Frequency range Health effects ELVs 1 Hz ≤ f < 3 kHz 1,1 Vm–1 (peak) 3 kHz ≤ f ≤ 10 MHz 3,8 × 10– 4 f Vm–1 (peak) Note A2-1: f is the frequency expressed in hertz (Hz). Note A2-2: The health effects ELVs for internal electric field are spatial peak values in the entire body of the exposed subject. Note A2-3: The ELVs are peak values in time which are equal to the Root-Mean-Square (RMS) values multiplied by √2 for sinusoidal fields. In the case of non-sinusoidal fields, exposure evaluation carried out in accordance with Article 4 shall be based on the weighted peak method (filtering in time domain), explained in the practical guides referred to in Article 14 but other scientifically proven and validated exposure evaluation procedures can be applied, provided that they lead to approximately equivalent and comparable results.

Sensory effects ELVs for internal electric field strength from 1 Hz to 400 Hz The sensory effects ELVs (Table A3) are related to electric field effects on the central nervous system in the head, i.e. retinal phosphenes and minor transient changes in some brain functions. Table A3 Sensory effects ELVs for internal electric field strength from 1 to 400 Hz Frequency range Sensory effects ELVs 1 ≤ f < 10 Hz 0,7/f Vm–1 (peak) 10 ≤ f < 25 Hz 0,07 Vm–1 (peak) 25 ≤ f ≤ 400 Hz 0,0028 f Vm–1 (peak) Note A3-1: f is the frequency expressed in hertz (Hz). Note A3-2: The sensory effects ELVs for internal electric field are spatial peak values in the head of the exposed subject.

Note A3-3: The ELVs are peak values in time which are equal to the Root-Mean-Square (RMS) values multiplied by √2 for sinusoidal fields. In the case of non-sinusoidal fields, the exposure evaluation carried out in accordance with Article 4 shall be based on the weighted peak method (filtering in time domain), explained in the practical guides referred to in Article 14, but other scientifically proven and validated exposure evaluation procedures can be applied, provided that they lead to approximately equivalent and comparable results. B. ACTION LEVELS (ALs) The following physical quantities and values are used to specify the action levels (ALs), the magnitude of which are established to ensure by simplified assessment the compliance with relevant ELVs or at which relevant protection or prevention measures specified in Article 5 must be taken:

— Low ALs(E) and high ALs(E) for electric field strength E of time varying electric fields as specified in Table B1;

— Low ALs(B) and high ALs(B) for magnetic flux density B of time varying magnetic fields as specified in Table B2;

— ALs(IC) for contact current as specified in Table B3;

— ALs(B0) for magnetic flux density of static magnetic fields as specified in Table B4. ALs correspond to calculated or measured electric and magnetic field values at the workplace in the absence of the worker. Action levels (ALs) for exposure to electric fields Low ALs (Table B1) for external electric field are based on limiting the internal electric field below the ELVs (Tables A2 and A3) and limiting spark discharges in the working environment. Below high ALs, the internal electric field does not exceed the ELVs (Tables A2 and A3) and annoying spark discharges are prevented, provided that the protection measures referred to in Article 5(6) are taken. Table B1 ALs for exposure to electric fields from 1 Hz to 10 MHz Frequency range Electric field strength Low ALs (E)[Vm–1] (RMS) Electric field strength High ALs (E) [Vm–1] (RMS) 1 ≤ f < 25 Hz 2,0 × 104 2,0 × 104 25 ≤ f < 50 Hz 5,0 × 105/f 2,0 × 104 50 Hz ≤ f < 1,64 kHz 5,0 × 105/f 1,0 × 106/f 1,64 ≤ f < 3 kHz 5,0 × 105/f 6,1 × 102 3 kHz ≤ f ≤ 10 MHz 1,7 × 102 6,1 × 102 Note B1-1: f is the frequency expressed in hertz (Hz).

Note B1-2: The low ALs (E) and high ALs (E) are the Root-Mean-Square (RMS) values of the electric field strength which are equal to the peak values divided by √2 for sinusoidal fields. In the case of non-sinusoidal fields, the exposure evaluation carried out in accordance with Article 4 shall be based on the weighted peak method (filtering in time domain), explained in the practical guides referred to in Article 14, but other scientifically proven and validated exposure evaluation procedures can be applied, provided that they lead to approximately equivalent and comparable results.

Note B1-3: ALs represent maximum calculated or measured values at the workers’ body position. This results in a conservative exposure assessment and automatic compliance with ELVs in all non-uniform exposure conditions. In order to simplify the assessment of compliance with ELVs, carried out in accordance with Article 4, in specific non-uniform conditions, criteria for the spatial averaging of measured fields based on established dosimetry will be laid down in the practical guides referred to in Article 14. In the case of a very localised source within a distance of a few centimetres from the body, the induced electric field shall be determined dosimetrically, case by case. Action levels (ALs) for exposure to magnetic fields Low ALs (Table B2) are, for frequencies below 400 Hz, derived from the sensory effects ELVs (Table A3) and, for frequencies above 400 Hz, from the health effects ELVs for internal electric field (Table A2).

High ALs (Table B2) are derived from the health effects ELVs for internal electric field related to electric stimulation of peripheral and autonomous nerve tissues in head and trunk (Table A2). Compliance with the high ALs ensures that health effects ELVs are not exceeded, but the effects related to retinal phosphenes and minor transient changes in brain activity are possible, if the exposure of the head exceeds the low ALs for exposures up to 400 Hz. In such a case, Article 5(6) applies. ALs for exposure of limbs are derived from the health effects ELVs for internal electric field related to electric stimulation of the tissues in limbs by taking into account that the magnetic field is coupled more weakly to the limbs than to the whole body. Table B2 ALs for exposure to magnetic fields from 1 Hz to 10 MHz

Frequency range Magnetic flux density Low ALs(B)[μT] (RMS) Magnetic flux density High ALs(B) [μT] (RMS) Magnetic flux density ALs for exposure of limbs to a localised magnetic field [μT] (RMS) 1 ≤ f < 8 Hz 2,0 × 105/f2 3,0 × 105/f 9,0 × 105/f 8 ≤ f < 25 Hz 2,5 × 104/f 3,0 × 105/f 9,0 × 105/f 25 ≤ f < 300 Hz 1,0 × 103 3,0 × 105/f 9,0 × 105/f 300 Hz ≤ f < 3 kHz 3,0 × 105/f 3,0 × 105/f 9,0 × 105/f 3 kHz ≤ f ≤ 10 MHz 1,0 × 102 1,0 × 102 3,0 × 102 Note B2-1: f is the frequency expressed in hertz (Hz). Note B2-2: The low ALs and the high ALs are the Root-Mean-Square (RMS) values which are equal to the peak values divided by √2 for sinusoidal fields. In the case of non-sinusoidal fields the exposure evaluation carried out in accordance with Article 4 shall be based on the weighted peak method (filtering in time domain), explained in practical guides referred to in Article 14, but other scientifically proven and validated exposure evaluation procedures can be applied, provided that they lead to approximately equivalent and comparable results.

Note B2-3: ALs for exposure to magnetic fields represent maximum values at the workers’ body position. This results in a conservative exposure assessment and automatic compliance with ELVs in all non-uniform exposure conditions. In order to simplify the assessment of compliance with ELVs, carried out in accordance with Article 4, in specific non-uniform conditions, criteria for the spatial averaging of measured fields based on established dosimetry will be laid down in the practical guides referred to in Article 14. In the case of a very localised source within a distance of a few centimetres from the body, the induced electric field shall be determined dosimetrically, case by case. Table B3 ALs for contact current IC Frequency ALs (IC) steady state contact current [mA] (RMS) up to 2,5 kHz 1,0 2,5 ≤ f < 100 kHz 0,4 f 100 ≤ f ≤ 10 000 kHz 40 Note B3-1: f is the frequency expressed in kilohertz (kHz). Action levels (ALs) for magnetic flux density of static magnetic fields Table B4 ALs for magnetic flux density of static magnetic fields