Electromagnetic fields

Your legal responsibility

Electromagnetic fields (EMFs) are produced whenever electrical or electronic equipment is switched on. You are legally required to:

• Establish the levels of EMFs to which your workers are exposed.
• Where necessary, undertake a risk assessment and record your findings.
• Ensure that the levels of exposure are below certain limits (known as exposure limit values).
• Ensure that you particularly consider workers who are pregnant and workers with implanted medical devices.
• Where necessary, create and keep a copy of an action plan to remove or reduce the exposure levels of EMFs and ensure compliance with the exposure limits.
• Provide information and training to workers of any particular risks posed by EMFs levels of exposure whenever you have a reason to suspect that they are no longer valid, or whenever there has been a significant change that can affect the exposure levels.
• Survey the health of, and provide medical examinations to, all workers who are exposed to EMFs above the exposure limit values and who report effects on their health. Appropriate records must be kept of the surveillance and/or medical examinations/reports.

Which laws apply?

• The Control of Electromagnetic Fields at Work Regulations 2016
• The Control of Electromagnetic Fields at Work Regulations (Northern Ireland) 2016

The health impact of electromagnetic fields

Exposure to EMFs can have long-term and short-term health effects that vary depending on the level of the frequency (measured in hertz) emitted by the equipment and duration of exposure. Health effects include:

• Physical effects - such as micro-shocks, burning of tissue or rise in core body temperature
• Sensory effects - such as nausea, vertigo, metallic taste in the mouth, buzzing noise
• Indirect health effects - such as electric shocks, interference with implanted medical devices, attraction to ferromagnetic devices causing objects to move and collide with someone

See EMFs.info for more information on what they are and known health effects.

Exposure and action levels

The regulations use 2 sets of values for measuring EMFs, exposure limit values (ELVs) and action levels.

ELVs are the legal limits of EMF exposure that is allowed to affect the inside of a worker's body. As EMF exposure limit values are usually impossible, or very expensive to measure, the regulations set 'action levels' that are easier to calculate.

If an action level is not exceeded, the EMF exposure limit value won't be exceeded and a risk assessment is not necessary. If an action level is exceeded, although it is possible that the EMF exposure limit value won't be, you will need to complete a risk assessment (and action plan).

Some action levels in the regulations represent levels where the indirect effects of EMF fields may start to occur.

Determining exposure and action levels

You must initially determine the level of exposure to EMFs of your workers.

You can use the following information to help you perform the assessment:

• Tables 2, 3, 5, 6 and 7 in the HSE guidance on the regulations and, in Northern Ireland, also the following EMF NI supplement (pdf)
• Evidence from your own records, such as reports of ill health by workers caused by EMFs
• Safety-related information, such as on emissions, provided by the manufacturer or distributor of the equipment
• Industry standards/guidelines provided for your industry sector, including information from trade associations and other organisations related to your industry sector
• Exposure databases (if available)

You must review the levels of exposure whenever:

• you have a reason to suspect that the last assessment is no longer valid; or
• there has been a significant change that can affect the exposure levels.