Electromagnetic field safety (EMF)

After repeated delays to the implementation of the 2004 European directive on workplace electromagnetic fields, a new directive has now been adopted and will come into force in 2016. Hugo Bibby looks at the implications for industry.

The European Union (EU) has long recognised the need to protect workers from the effects of electromagnetic fields (EMFs) in the workplace and in 2004 published a directive laying down minimum health and safety requirements regarding exposure to them.However, the original measure, Directive 2004/40/EC, met with sustained opposition, primarily from the medical community across Europe, which expressed serious concerns that the strict exposure limits set out in the directive would hamper the use of MRI (magnetic resonance imaging) technology.Faced with this resistance, and wider concerns from a number of industry sectors, implementation of the directive was repeatedly delayed.

Eventually in June 2013, the original directive was formally repealed and replaced with Directive 2013/35/EU, which according to the EU, “reviews exposure limitations on the basis of new scientific evidence and provides for derogations, in particular for medical applications using magnetic resonance imaging”.

Member states are now required to transpose this directive into their national legislation by 1 July 2016.

So, how will the health and safety landscape be altered when the directive becomes law? Like the original measure, the new directive does not cover the general public but only workers while they are engaged in their professional duties. Although guidelines already exist regarding exposure to EMFs in the workplace – notably from the International Commission on Non-Ionizing Radiation Protection – in 2016 there will be mandatory limits for the first time.

Most organisations will not actually be affected very much by this change. Admittedly, every employer will be obliged to undertake an EMF risk assessment, but in the majority of cases no further action will be required.

However, there are some industries that definitely will be in the spotlight and will need to introduce measures to reduce workers’ exposure to EMFs. Wherever a process utilises EMFs or where equipment operates at high voltage or high current levels, employers need to gain a deeper understanding of the issues involved and carefully examine the requirements of the new directive.

This is likely to impact organisations operating in sectors such as electricity supply, metals and manufacturing, automotive and, of course, healthcare. While high EMFs also routinely occur in broadcast and telecommunications workplaces, these sectors have long been aware of the issue and all the major operators already have appropriate measures in place.

Health risks
So, what exactly are the health risks associated with exposure to EMFs? Although some long-term effects have been suggested, these are specifically excluded from the directive, as there is currently no conclusive evidence of any causal relationship. However, the directive does cover short-term direct biophysical effects, which are scientifically well established, as well as indirect effects such as interference with cardiac pacemakers.

The direct biophysical effects are broadly categorised as thermal effects, such as heating of tissue through absorption of energy from EMFs, and non-thermal effects, such as the stimulation of muscles, nerves or sensory organs. In general terms, thermal effects tend to occur at higher frequencies, above about 100kHz, while non-thermal effects are characteristic of lower frequencies, typically below 10MHz. Between 100kHz and 10MHz, both thermal and non-thermal effects may be evident.

Exposure limits
In seeking to limit workers’ exposure to EMFs, the directive uses the terms action levels (ALs) and exposure limit values (ELVs). As the name suggests, ALs are not limits but levels which, if exceeded, indicate that further action is necessary, typically ensuring that the ELVs are not exceeded and measures are introduced to reduce exposure. Such measures might include the use of signs and access restrictions, shielding of equipment, and changes to working practice such as limiting the duration and intensity of the exposure. ELVs, meanwhile, are limits that should not be exceeded. Most organisations, even those working with reasonably high power equipment, will be able to use the ALs as their maximum permissible exposure levels and are unlikely to ever have to use the higher ELVs.

This is all relatively simple and in line with the desire to ensure a proportionate approach to better protect workers exposed to EMFs while not increasing the regulatory burden on businesses.

However, in some instances – particularly for low-frequency exposures – the situation is more complex. For example, users of industrial processes with high levels of current will find that the resulting magnetic field can be significant, so below 10MHz the directive lists both low and high ALs and, for magnetic fields, an even higher level for exposure of limbs.

Furthermore, below 400Hz, ELVs are listed for sensory effects as well as health effects. ‘Sensory effects ELVs’ are those above which workers might be subject to transient disturbed sensory perceptions and minor changes in brain functions, whereas ‘health effects ELVs’ are those above which workers might experience symptoms such as heating or stimulation of nerve and muscle tissue.

The directive permits the sensory effects ELVs to be temporarily exceeded, but the health effects ELVs may only be exceeded under the terms of the derogations or exemptions, which specifically mention MRI.

Training
Since the sensory ELVs may be exceeded, workers need to be aware of the possible effects. Even relatively common processes such as welding may exceed High and Limb ALs, so training in how to reduce exposure is of great importance. The directive therefore requires employers to give exposed workers the necessary information and training, particularly relating to the outcome of the risk assessment, the measures taken by the employer, safe working practices, the detection of adverse effects and the circumstances in which workers are entitled to health checks.

Within the directive, there is also specific emphasis on provisions for pregnant workers and those with implanted or body-worn medical devices, such as pacemakers or insulin pumps, all of which should be encompassed by any risk assessment or training.

Practical guide
To assist employers with the EMF risk assessment process and implementation of the directive, Public Health England is preparing a non-binding practical guide, which will be freely available by 1st January 2016. This publication will not only help the majority of employers to quickly recognise they do not have a problem with EMFs but will also provide more detailed guidance for employers who do have higher fields in their workplace. In particular, it will cover the determination of exposure, including calculation methods for the assessment of ELVs and a description of the ‘weighted peak method’ for measuring low-frequency fields.

Measurements
The best course of action for most organisations at present is to start developing in-house knowledge of EMFs and the provisions of the directive. Although that might appear daunting to some, in truth anyone who routinely deals with say noise and vibration in the workplace should be able to get to grips with the subject matter without too much difficulty.

In due course, EMF exposure will need to be assessed, and if compliance cannot be reliably determined on the basis of readily accessible information, it will be necessary to carry out measurements and/or perform calculations.

EMFWeld
Some parts of industry have taken a proactive approach to the impending legislation as they will be under especially close scrutiny when the directive takes effect. For example, in the metal fabrication sector, the EMFWeld project1 has been set up in recognition of the fact that some welding and non-destructive testing processes are high emitters of EMFs.

This EU-funded project aims to reduce the cost of compliance with the directive for SMEs by developing a software application to calculate and assess workers’ exposure to EMFs. The software will provide simple yet effective and actionable information regarding the risk to workers using any particular machine, indicating whether there is no risk whatsoever or whether exposure is likely to be below or above the limit imposed by the directive.

Despite the troubled history of the EMF Directive, the measure will now enter the statute books in 2016. Health and safety professionals would be well advised to obtain a copy of the practical guide as soon as it is published so that any necessary remedial action can be taken before the directive becomes law.

Hugo Bibby is technical director of EMF safety specialist Link Microtek

Reference
1. The EMFWeld project has received funding from the European Community’s Seventh Framework Programme managed by REA-Research Executive Agency (FP7-SME-2012) under grant agreement no. 315382.