Hazards of Ionising and Non-Ionising Radiations

  • General radiation hazards


    The Health Protection Agency, (formerly the National Radiological Protection Board), have an excellent series of interactive modules.

    Modules for Radon, Transport of Radioactive Materials, Nuclear Emergencies, Radio-Waves and Doses from Discharges currently exist, along with an electronic version of the HPA Sunsense poster. Future modules include Electric and Magnetic Fields, Ultraviolet Radiation and Maps and Magnitudes.

  • Radioisotopes


    There are two categories of radioactive material, closed and other.

    Closed sources are sources in which the radioactive material is contained within a permanently sealed housing or is permanently bonded to a surface or foil.

    Other sources are all sources that are not closed sources. These are normally sources that are supplied as a liquid or powder and which are therefore dispersible once the containment vial has been opened

    The hazard from radiation emitted by radioisotopes varies according to decay emission (Alpha, Beta, Gamma or Neutron) and the emission energy. For the most common radioisotopes used in the University the hazards are listed in Isotope Hazards. Local Rules are required for each registered radiation laboratory. Local Rules within the University of Liverpool are divided into three sections. Document LR1 is General Local Rules applicable throughout all laboratories within the university. Document LR2 is General Contingency Plan applicable throughout the univeristy. Document LR3 is Local Rules specific to a particular department or section thereof. LR1 and LR2 can be found on the Documentation page of this site together with a Template for LR3

    All persons using radioisotopes must be registered with the Radiation Protection Office (Registration).

  • X-Rays

    • The electromagnetic radiation from X-rays is only emitted when the X-ray unit is energised and the shutter opened. There is no radiation hazard when the X-ray unit is off.
    • Emission from the X-ray unit is usually limited by collimator to a specific beam size. Persons outside the beam path may receive scattered x-radiation from the target in the beam path.
    • In the case of diagnostic X-ray units the scattered x-radiation to the critical organs may be significantly reduced by wearing lead equivalent aprons.
    • In the case of crystallography units the beam should be totally enclosed within an interlocked housing. There is then no hazard to workers outside the housing.
    • All persons using X-ray units must be registered with the Radiation Protection Office.

    X-ray Safety

    If you are worried about the safety implications of having an x-ray you can download a safety leaflet here.

  • Pregnancy


    To enable the University to accept its responsibility for the welfare of the new baby the mother-to-be must notify the University as soon as the pregnancy is confirmed. This should be done, in writing, to the Head of Department.

    For the majority of mothers-to-be there will probably be no requirement to alter their job/research practices as the radiation doses received during the pregnancy will be well below the permitted limit (1mSv) for the foetus. However it may be desirable to limit the handling of stock materials of the higher energy Beta and Gamma emitting sources. Advice may be obtained from the Radiation Protection Office.

    The HSE have published an excellent and informative document entitled Guidelines for expectant or breast-feeding mothers. These guidelines give advice on how expectant and breast-feeding mothers may work safely with ionising radiation. The document can be downloaded in PDF format

    The HSE also has a website entitled Health and Safety for new and expectant mothers which has much information for the new and expectant mother about general safety at work during pregnancy.

  • Mobile phones


    Available for download are:

  • Microwaves


    High frequency electromagnetic fields are known as microwave radiation. The main effect of exposure to such radiation is heat deposition in tissue. The most obvious result of this heating effect has been shown to be the temporary disruption of learned behaviour in animals. The average level of specific absorption rate required to produce temporary disruption has been shown to be 2 - 8 Watts per kilogram. The Health Protection Agency, (formerly the National Radiological Protection Board), has therefore recommended a maximum exposure level of 0.4 Watts per kilogram. Although some work with microwave transmission is conducted in the Department of Electrical Engineering and Electronics and in the Department of Physics, the main use of microwave radiation within the University is in microwave ovens.

    All microwave ovens, whether used for heating in experiments such as agar solutions or for domestic cooking, must be registered with the Radiation Protection Office. The information required is Manufacturer, Model, Serial Number, Department, Room/Lab Number. This information may be sent as an e-mail.

  • UV radiation


    Ultra Violet radiation lies within the wavelength range 100 - 400nm. The direct effects are limited to the skin and eyes because of its non-penetrating nature. There are acute effects such as erythema (sunburn) of the skin and conjunctivitis of the eye and chronic effects such as premature skin ageing, skin cancer and cataracts of the eye.

    The UV wavelengths are divided into three sections:

    • UVA - 400-315nm
    • UVB - 315-280nm
    • UVC - 280-100nm

    The most common sources of UV radiation within the University are UV Reactors (for accelerating or inducing chemical reactions), germicidal lamps (for sterilising benches or flow cabinets), and transilluminators. All these use lamps having shorter wavelengths than the UVA lamps used in most sunbeds and the effect of exposure on skin or eyes may be noted after very short inadvertent exposure. In no circumstances should any part of the body be exposed to the UVB and UVC radiation from reactors, germicidal lamps or transilluminators.

    Units containing germicidal lamps should be interlocked to prevent access whilst the lamp is on. Transilluminators must be used with gauntletted gloves and must be used with either the fitted perspex UV shield or separate full face shield. Local Rules for work with UV radiation are available from Radiation Protection Office and may be downloaded in WORD or PDF format.

  • Cosmetic tanning


    The Health Protection Agency, (formerly the National Radiological Protection Board), have issued Information on Sunbeds and Cosmetic Tanning which provides warning on the use of sunbeds and other cosmetic tanning.

    The International Commission on Non-Ionising Radiation Protection have issued a paper on the Health Issues of Ultra Violet Tanning Appliances used for Cosmetic Purposes

  • Lasers


    The most vulnerable organs from laser light are the eyes. Light from a laser is concentrated into a narrow beam. This beam can be further concentrated by the lens of the eye onto the retina and cause temporary or permanent blindness. The blink reflex of the eye will normally protect the eye from a Class 1 laser but care must be used in the design of an experiment to ensure that light from Class 2 (and higher Class) lasers cannot impinge upon any person's eye.

    Guidance Notes for Users of Lasers in Education and Research issued by the Association of Unervsity Radiation Protection Officers may be downloaded here

    • It is policy among most universities in the UK that laser pointers used in lecture theatres are limited to Class 1 or Class 2.
    • Laser Safety Code of Practice, Generic Laser Local Rules and Generic Laser Risk Assessment are available on the Documentation page
    • Lasers (other than laser pointers) must be registered with the Radiation Protection Office and the laser form in Documentation should be used (Registration of Laser)

    Laser pointers

    The Health Protection Agency, (formerly the National Radiological Protection Board), have issued an Information Sheet on Laser Pointers. Please also read Note on Laser Pointers issued by University Radiation Protection Advisor.