Last reviewed 5 July 2016
On 1 July 2016 the Control of Electromagnetic Fields at Work Regulations 2016 (CEMF), which implement the EMF Directive (2013/35/EU), come into force. Gordon Tranter outlines the regulations’ requirements and their likely impact in the workplace.
What are electromagnetic fields?
An electromagnetic field (EMF) is produced whenever an item of electrical or electronic equipment, eg televisions, microwave ovens, computers and mobile phones is used. An EMF is defined by the CEMF as a static electric, static magnetic and time-varying electric, magnetic and electromagnetic field with a frequency of up to 300GHz. EMFs are present in virtually all workplaces and, if they are of high enough intensity, it may be necessary to take action to ensure that workers are protected from any adverse effects.
Minimise the risks to workers
The CEMF require employers to assess and limit the levels of EMFs to which their workers are exposed and minimise the risks to workers arising from exposure to EMFs. This does not include long-term effects.
The effects of EMFs
The effects on workers of exposure to EMFs depend on the frequency range and intensity of the EMFs to which they are exposed. EMFs at different frequencies affect the human body in different ways, causing sensory and health effects. The majority of EMFs do not pose any risk, although those with greater field strengths can have short-term adverse effects on the body.
Low frequencies: up to 10MHz can affect the nervous system and below 1Hz can affect the heart.
High frequencies: 100kHz and above cause heating effects on the whole body or parts of it. Exposure to strong EMFs may result in feelings of vertigo or nausea, and electric shocks or burns may be sustained from touching ungrounded conducting objects in an electromagnetic field.
EMFs can also have indirect effects that can be a health and safety hazard. Ferromagnetic objects within a large static magnetic field could be attracted to the magnet and hit and injure someone. In addition, some EMFs can have effects on active or passive implanted medical devices, eg cardiac pacemakers, or medical devices worn on the body, eg insulin pumps. Radio frequency fields can cause ignition of flammable vapours and gases, and initiation of electro-explosive devices.
Table 1 in the Health and Safety Executive (HSE) HSG281 Electromagnetic Fields at Work: A Guide to the Control of Electromagnetic Fields at Work Regulations 2016 provides examples of effects which may be produced by work activities and equipment in the different frequency ranges.
Magnetic Resonance Imaging
Directive (2013/35/EU) on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (electromagnetic fields) (the EMF Directive) was originally issued as Directive 2004/40/EC. However, this directive was not brought into law because of concerns about the potential negative impact on the use and development of certain Magnetic Resonance Imaging (MRI) activities. Further concerns were also raised across a number of industries over the directive’s requirement for complicated and costly risk assessments. The latest directive includes derogations for MRI equipment for patients in the health sector and military activities, and limited derogations for industrial activities.
The risk assessment
The risk assessment required by the CEMF involves:
identifying EMF sources present in the workplace, using practical guides, standards, guidelines, databases and manufacturers’ data
determining compliance of the equipment by reference to above data or perform measurements and/or calculations
taking account of EMF frequency, level and duration; the type of exposure, its distribution over the body and over the workplace; and multiple sources and multiple frequencies of EMFs
identifying direct effects (health) and indirect effects (eg medical devices, projectiles, electro-explosive devices, flammable materials, shock/burn contact currents)
identifying workers at particular risk (eg with medical devices, pregnant workers)
comparing results to exposure limits values and action values (see below).
The risk assessment should be recorded and where the exposure limits values and/or action values are exceeded, an action plan should be prepared and implemented.
Action levels and exposure limit values
The CEMF are based on two sets of physical quantities: action levels (ALs) and exposure limit values (ELVs). These are based on the recommendations of the International Commission on Non-Ionizing Radiation Protection.
The ELVs are specified in terms of an electric field induced in the body. Two ELVs are of importance: the “sensory effects ELVs” and “health effects ELVs”. The sensory effects ELV defines the limits above which workers may experience temporary sensory perceptions, such as retinal phosphenes (seeing stars) or vertigo or subtle changes in decision-making and reasoning. The health effects ELV defines the limits above which workers might experience adverse health effects, eg thermal effects or direct stimulation of tissues.
ELVs are the legal limitations on the exposure of employees to EMFs; the limits that employers need to ensure that the exposure of employees is kept below. As they are specified in terms of an electric field induced in the body they are usually very difficult, and expensive, to measure directly. For this reason, a separate set of exposure values ALs have been produced, which can be measured more easily and compliance with these ALs will ensure compliance with the relevant ELVs.
The action plan
Once it has been determined that the relevant ALs are likely to be exceeded and/or if it has been shown that the ELVs are not exceeded, the employer must devise and implement an action plan. This plan should set out steps required to eliminate or minimise the risks. The technical and/or organisational measures to prevent exposure exceeding the health effect ELVs and sensory effect ELVs include:
zoning, barriers and signs
locking off access (doors, roof access, towers)
designing the layout of the workplace
interlocks and equipment shielding
other working methods that give less exposure
equipment that emits less intense EMFs
limiting the duration of exposure
personal protection equipment (radiation meters, personal alarms and shielded clothing).
Workers at particular risk, such as expectant mothers and workers with active or passive implanted or body worn medical devices, must be taken into account.
Information and training on the particular risks posed to employees by EMFs in the workplace and details of any action that are being taken to remove or control them should be provided to those likely to be exposed.
The CEMF only relate to short-term effects resulting from exposure to EMFs. They do not address the long-term effects, including the carcinogenic effects, that could result from exposure to EMFs, for which there is no conclusive scientific data establishing a causal link. Consequently, health surveillance is only likely to be necessary in very limited circumstances. Where an employee reports experiencing a health effect, and that employee is exposed to EMFs exceeding any ELV, health surveillance and medical examinations should be provided as appropriate.
Workers should be trained on how to detect adverse health effects of exposure, how to report them and the circumstances in which they are entitled to health surveillance.
The impact of the CEMF
The risks from EMF are generally already well understood and many are covered by existing legislation. The most notable impact of the new regulations will be a specific requirement on employers to assess the levels of EMFs to which their workers may be exposed, against ALs and/or ELVs.