Every day in the UK, a wide range of radiation types are used in industrial, medical, research and communications applications. Some of these cause harmful exposure risks that must be adequately controlled. This Toolbox Talk explains how to manage those controls
Dangers of radiation – case study 1
A scrap metal dealer bought a hand-held X-ray fluorescence analyser (sometimes called an XRF gun) to analyse the alloy content in scrap. These guns produce an intense beam of X-ray radiation at the front of the equipment, and also result in a scattering of X-rays when they hit the test material.
When used properly, pointing away from the body, the radiation risks to operators and others will be minimal. However, if the equipment is damaged, incorrectly set up, or misused, there is the potential for exposure to high-radiation fields.
How the Problem was Solved
The manager of the scrap yard consulted a radiation protection adviser (RPA), who assisted the company in carrying out a risk assessment. This recommended that workers were trained in how to use the analyser safely and not to operate the gun without covering the X-ray aperture, or to hold the item being tested in their hand.
Users were also trained in what to do if the analyser was dropped or damaged. They were advised to buy an interlocked test box from the suppliers so they could test small parts safely. The RPA also agreed to measure the dose rates of the device in use to help the business meet its legal requirements.
By taking this action, the employer ensured that his workers and others were protected.
What are the main types of radiation?
Radiation is generally classed as ‘ionising’ or ‘non-ionising’, with the former generally having more energy than the latter.
These include X-rays, gamma rays and particulate radiation (alpha, beta and neutron radiation) produced from X-ray sets or radioactive substances.
They are typically used in medical assessments, industrial radiography equipment and gauges used in industry for process control, but may also be produced from naturally occurring radioactive substances, including radon gas.
- Radio frequency and microwaves, e.g. from plastic welding and some communications transmitters.
- Infra-red, e.g. from very hot, glowing sources in glass and metal production.
- Ultraviolet (UV) rays, eg from welding or the sun.
- Visible radiation from high-intensity light sources, eg lasers.
Dangers of radiation – case study 2
After media reports claiming some homes were prone to radon, the manager of a local engineering firm was approached by a number of workers wanting assurances that they were not at risk while at work.
The manager used the Health Protection Agency's website to confirm the premises were in a Radon Affected Area, and that many employees spent their working day in ground-floor rooms, where radon gas is more likely to accumulate.
How the problem was tackled
The manager used HSE’s guidance to carry out a radon assessment, which included making measurements. The results showed very high levels (and possibly significant radiation doses) in two rooms.
He consulted a radiation protection adviser on how to reduce his employees' exposures. Following this, he contacted a radon remediation specialist, who quickly installed a simple, underfloor sump/extract system to prevent the gas entering the premises.
Repeat measurements showed this was extremely effective in affording long-term protection, as the levels of radon were now very low.
Ionising radiations can cause dermatitis, burns, cell damage, cataracts and changes to blood.
Microwaves and radio frequencies can cause heating of any exposed part of the body, infra-red rays can cause skin burns and cataracts and UV light can cause skin burns, skin cancer, conjunctivitis and arc eye. Lasers can cause permanent, severe damage to the eye and skin.
Exposure to ionising and UV radiation can damage DNA and can cause health effects, such as cancer, later in life. The risks are small for low levels of exposure but exposure to high levels of ionising and non-ionising radiations can cause acute effects such as burns, tissue and organ damage.
What do I have to do?
Identify all sources of ionising and non-ionising radiation in your workplace and the risks they pose. Once you have identified the significant risks, you must control them.
Try and reduce any exposure to ionising and UV radiation. For example, you may be able to use safer alternative processes or equipment, eg ultrasonic, non-destructive testing instead of X-rays.
Dos and don’ts of radiation safety
- Make sure you know the different potential sources of radiation in your workplace, particularly all sources of ionising radiations, UV light and high-power lasers.
- Consider asking for advice from a radiation protection adviser (RPA); this is a legal requirement when working with ionising radiations. Names and contact details of RPAs can be found on the HSE radiation website.
- Consider whether staff should be subject to medical surveillance – an RPA will help with this.
- Consider radon gas exposure in your risk assessments. This is naturally occurring and may be present in your workplace even if you don’t do any other work with radiation.
- Ensure adequate shielding and personal protective equipment is used to reduce exposure when working with ionising radiation and to protect the skin and eyes when working with hazardous sources of infra-red (eg molten metal) and UV (e.g. welding).
- Seek expert advice where lasers are used for displays (e.g. bars, nightclubs and stage shows) and there could be a risk to the public.
- Override any interlocks preventing access to high-voltage electrical equipment, X-ray cabinets, laser enclosures or machinery containing lasers.
- Use potentially harmful germicidal UV lamps as replacements in otherwise safe insect-killing devices or other fluorescent light fittings. Make sure you replace these with the correct type specified by the manufacturer.
If your work with ionising radiations could produce a radiation emergency (ie an event that could lead to a member of the public receiving a dose of ionising radiation above certain levels) the Radiation (Emergency Preparedness and Public Information) Regulations 2001 may apply.
- The Control of Artificial Optical Radiation at Work Regulations 2010 require businesses with hazardous sources of bright light (eg lasers, welding processes) to ensure the eyes and skin of their workers are protected.
- The Ionising Radiations Regulations 1999 apply to most work with ionising radiations, including exposure to naturally occurring radon gas.