Radiation Protection Today - Winter 2022 Issue 4 - Page 30

Specialist Spotlight –

Non-Ionising Radia on ( NIR )

In addition to his role as a Radiation Protection Adviser ( RPA ) and Medical Physics Expert ( MPE ), David Rawlings has a strong interest in nonionising radiation safety and is an accredited Laser Protection Adviser ( LPA ). He is Chair of the SRP EMF and Optical Radiation Committee .
Many of us may be familiar with the benefits , hazards and regulations associated with Ionising Radiation . But there is a similar field calling for understanding and regulation .
What is non-ionising radiation and how does it differ from ionising radiation ? Ionising radiation ( i . e . X-rays , gamma rays , proton beams and similar ) can act directly on DNA causing double strand breaks with the potential for both acute and long term harm . Other forms of radiation ( e . g . ultra-violet , laser , infra-red , time varying or static electromagnetic fields , etc .) do not cause double strand breaks directly but can nevertheless have a deleterious impact on health where levels of exposure are high . This latter group is referred to as non-ionising radiation .
Electro-magnetic fields ( EMF ) and optical radiation represent the two main types of non-ionising radiation :
EMF radiation is produced by a variety of sources including substations , high voltage power lines , mobile phone masts and the like . Exposure to members of the public is generally well controlled and subject to continued monitoring and ongoing research . Provided that exposure is kept below recommended thresholds , no significant health effects are anticipated although in the UK some additional precautionary measures have been suggested in relation to mobile phone use .
There are also a variety of other specialist areas , such as industry , research , medicine and the military that make use of EMF radiation generating equipment . These usually have the potential for higher levels of exposure and additional measures are often required to protect members of staff and ' workers at particular risk ' ( cardiac pacemaker , ICD ( defibrillator ) wearers , pregnant workers etc ).
Optical radiation includes ultra-violet , visible , infra-red and laser beams . Sources of public exposure include artificial lighting , laser products , entertainment displays , heat lamps , tanning studios and the sun . While some controls exist , the potential for acute and long-term harm remains . A large range of specialist optical radiation-producing devices exist , many of which are highly dangerous if used inappropriately . These include lasers for military , industrial or medical use . In these cases it is likely that special control measures will be required . These may include engineering solutions , such as access control , administrative measures ( e . g . local rules ) and personal protective equipment ( e . g . goggles ).
How is non-ionising radiation regulated ?
An example of a mobile phone mast
30 Radiation Protection Today www . srp-rpt . uk