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Practical Implementation of the “EMF” EU Directive by an electrical company. Francois DESCHAMPS – France – RT 2c. General introduction to the Directive 2004/40/CE Exposure limit values Risk assessment process. Implementation in RTE : risk analysis and risk management policy.
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Practical Implementation of the “EMF” EU Directive by an electrical company Francois DESCHAMPS – France – RT 2c
General introduction to the Directive 2004/40/CE • Exposure limit values • Risk assessment process • Implementation in RTE : risk analysis and risk management policy
Applicable to central nervous system Provided that ELV are not exceeded Forbidden exceeding Allowedexceeding • Exposure Limit Values Basic Restrictions • Action Values Reference Levels
COMPLIANT no AV AV exceeded ? ELV exceeded ? yes Organizational or technical measures Reduce exposure or Further assessment COMPLIANT no VLE yes NOT COMPLIANT exposure mitigation requested Organizational or technical measures Risk Analysis : exposure assessment Employer settles an action plan
General introduction to the Directive 2004/40/CE • Implementation in RTE : • Risk analysis • General results • Risk management policy regarding live-line working
AV exceeded ? Measures to reduce exposure C Current 1 mA 50 Hz MF 500 µT yes yes yes 50 Hz EF 10 kV/m Further assessment Risk Analysis :exposure assessment in RTE Settlement of an action plan
Compliance assessment results • Exposure to 50 Hz electric field Work positions in HV substations and towers Compliant with standardisation limits (IEC 62226-3.1 and draft CENELEC WG17) • Exposure to contact currents • Compliant provided simple organizational measures • Grounding of vehicles in HV substations • Workers with security shoes (non conducting) • Exposure to 50 Hz magnetic field • Apart from close vicinity situations Compliant • Spot sources (coils) Access restricted by fences
I • Exposure to magnetic field during live-line working Simple source For I = 1000 A B = 500 µT (AV) at d = 0,4 mB = 200 µT at d = 1,0 m B = 100 µT at d = 2,0 m • No concern as far as electrical security distances are respected • Further assessment required for live-live working at contact
Exposure to magnetic field during live-line working Further assessment : human dosimetry,i.e. computation of induced currents in the body using sophisticated models NORMAN Modelling of “worst case” of exposure situations
I • Exposure to magnetic field during live-line working Result of the detailed exposure assessment : definition of a magnetic field limit on the basis of the “worst case” exposure situation, i.e. the lowest field magnitude which meets the 10 mA/m² limit in the CNS • How to check compliance to this limit ? • 2 possible actions : • Lowering the current I ? • Increasing the distance d Monitoring of the current Increasing the distance
Compliance assessment results : General conclusion • Exposure to 50 Hz electric field Work positions in HV substations and towers Compliant with standardisation limits (IEC 62226-3.1 and draft CENELEC WG17) • Exposure to contact currents • Compliant provided simple organizational measures • Grounding of vehicles in HV substations • Workers with security shoes (non conducting) • Exposure to 50 Hz magnetic field • Apart from close vicinity situations Compliant • Spot sources (coils) Access restricted by fences • HV live-line working • Live-line working is not questioned the EU Directive 2004/40/EC • Exceeding the limit values is only possible under unusually severe exposure conditions : head at contact of a live wire + heavy load • Such conditions can be managed using simple working rules