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FAQs – Ionising radiation

What is the difference between ionising and non-ionising radiation?

The main difference between ionising and non-ionising radiation is in the amount of energy the radiation carries. Ionising radiation carries more energy than non-ionising radiation.

Ionising radiation includes: X-rays, gamma rays, radiation from radioactive sources and sources of naturally occurring radiation, such as radon gas. Ionising radiation has many uses in industry, such as energy production, manufacturing, medicine and research and produces many benefits to society. However, it is important that the risks of ionising radiation are managed sensibly to protect workers and the public.

Non-ionising radiation includes: visible light, ultra-violet light, infra-red radiation, and electromagnetic fields. Sources of electromagnetic fields are used extensively in telecommunications and manufacturing with little evidence of related long-term health problems. Ultra-violet light is part of natural sunlight and also forms part of some man-made light sources. It can cause a number of health problems, including skin cancer.

Further information on ionising and non-ionising radiation can be obtained from the Health Protection Agency (HPA).

What kind of industries use ionising radiation?

The use of ionising radiation covers the use of radioactive materials and radiation generators in work activities. Ionising radiation sources are used in the following industries:

HSE regulates work with ionising radiation to ensure that workers and members of the public are not harmed by these activities. The Nuclear industry is regulated by the Office for Nuclear Regulation.

Notification

When and how do I notify HSE of my intention to work with ionising radiation?

Employers planning to carry out work with ionising radiation are required to notify HSE at least 28 days before they start work. See the radiation notifications webpages for further details on how to notify HSE and what information to include.

My organisation is using ionising radiation. How can I find out if they have notified HSE?

Whenever an organisation notifies HSE, they must retain details of how/when this was made and to which work it relates. Keeping a copy for reference will also help your organisation, should they need to notify HSE of any changes.

I can’t find details of my notification. Can HSE help?

If you’re unsure whether you have notified HSE or have lost your notification details, there are occasions where HSE may be able to help. In such instances, you can contact HSE by email at: irrnot@hse.gsi.gov.uk

Do I need to notify HSE of any changes to my work?

You must notify HSE if there are any material changes to the work details you previously notified us about. For information on the types of changes you need to inform us about, and the details we need, see the radiation notifications webpages.

Do I have to notify neighbouring premises of my work with ionising radiation?

If your prior risk assessment or “hazard identification and risk evaluation” showed that no radiation hazards exist in neighbouring premises as a result of your work activities – including reasonably foreseeable radiation incidents, accidents and emergencies – then there is no legal requirement for you to inform them (for more information on hazard identification and risk evaluations please see the REPPIR webpages). It is a legal requirement for employers to ensure that they do not create risks of significant radiation exposure from their normal work with radiation in areas not under their control. If a radiation accident or emergency could result in significant exposure of neighbours then they will need to be made aware of what to do in such an event to limit their exposure.

If two employers share the same workplace, whether on a temporary or permanent basis, they have to co-operate and co-ordinate the measures they take in complying with the law. This co-operation includes informing each other of any risks to employees arising from their work.

Do I need to notify HSE each time I perform site radiography?

Yes. You are required to notify HSE at least seven days in advance of each proposed site radiography job. For further information on site radiography notifications, see the radiation notifications webpages.

Do I need to notify HSE when importing equipment?

If you import electrical equipment that produces ionising radiation (e.g. equipment that produces X-rays), and intend to use this at work, you must notify HSE at least 28 days before starting the work.

If you are importing equipment that produces ionising radiation for resale or supply, then you have a duty to ensure that you supply your customers with sufficient information to enable them to comply with the Ionising Radiation Regulations 1999.

If you are planning to import radioactive substances (either as a sealed source or in an unsealed form), you should notify HSE 28 days in advance of the substances arriving at your premises. You will probably also require a special permit / licence from an environment agency for holding radioactive substances (as required under environmental legislation).

Radiation Protection Advisers

What are Radiation Protection Advisers (RPAs)?

A Radiation Protection Adviser (RPA) is an individual or body which provides advice to employers on compliance with the Ionising Radiations Regulations 1999.

Do I have to consult a Radiation Protection Adviser (RPA)?

If you are an employer working with ionising radiation (a ‘radiation employer’), you will need to consult a suitable Radiation Protection Adviser (RPA). Any RPA consulted should conform to the definition of an RPA as described in HSE’s criteria of competence and should be suitable in terms of possessing the requisite knowledge and experience relevant to the employer’s type of work.

What qualifications and experience should a Radiation Protection Adviser have?

A Radiation Protection Advisor (RPA) should meet the requirements described in HSE’s criteria of competence. An RPA must also have relevant knowledge and experience for the employer’s type of work. For further information, see the Radiation Protection Advisers webpages.

What should I consult a Radiation Protection Adviser (RPA) about?

Employers working with ionising radiation need to consult an RPA, with relevant knowledge and experience for the employer’s type of work, on how to comply with the Ionising Radiations Regulations 1999. For information on the specific things you need to consult an RPA on, see the Radiation Protection Advisers webpages.

How can I find a suitable Radiation Protection Adviser (RPA)?

For a list of recognised radiation protection advisers (RPAs), please see the Society for Radiological Protection's website. For a list of HSE-recognised RPA bodies, see RPA bodies recognised by HSE.

Doses

What are dose limits?

Dose limits are intended to reduce the risk of serious effects occurring, such as cancer, and are in place to protect the eyes, skin and extremities against other forms of damage. Dose limits are defined in UK legislation and can be found in schedule 4 of the Ionising Radiations Regulations 1999.

Why have dose limits?

Dose limits are set to protect workers and members of the public from the effects of ionising radiation. They are set at a level that balances the risk from exposure with the benefits that use of ionising radiation brings.

Are there different dose limits for different people?

Yes. There are different dose limits for different classes of people, as follows:

There are also additional dose limits for women of reproductive capacity and those who are pregnant or breast-feeding.

Should I notify my employer if I am pregnant?

It is in the interests of both yourself and your baby to inform your employer as soon as you know you are pregnant. Your employer needs to know this so they can make any necessary changes to protection measures and apply the additional dose limits. You are not legally required to inform your employer and can choose to keep this private. However, if your employer is unaware that you are pregnant they may not be able to take any further action.

See: Working safely with ionising radiation: Guidelines for expectant or breastfeeding mothers for more information.

Am I allowed to exceed a dose limit?

It is an offence under the Ionising Radiations Regulations 1999 to exceed a dose limit. If the Radiation Emergency Preparedness and Public Information Regulations 2001 (REPPIR) apply to your premises, you may adopt higher dose limits (if previously agreed with HSE) for use in the event of an emergency.

Further information on higher dose limits please see the REPPIR Approved Code of Practice and guidance

Accidents and emergencies

What kind of radiation incidents do I need to report to HSE?

An employer working with ionising radiation is required to notify HSE when:

For information on emergency notification to HSE, see the radiation notifications webpages.

What are the Radiation Emergency Preparedness and Public Information Regulations 2001 (REPPIR)?

REPPIR applies to operators of premises who carry out work with ionising radiation, and to those who transport radioactive sources through public places – other than by standard forms of transport – in excess of specified levels. The main aim of the Regulations is to establish whether a radiation emergency is foreseeable and to mitigate the consequences, should one occur.

For further information, see REPPIR Approved Code of Practice and guidance

Equipment testing

How frequently should I undertake leak tests on my radiation sources?

A leak test should normally be performed at least once every two years, although more frequent testing is recommended:

At what intervals should radiation equipment be inspected?

There is no set time interval for inspecting and maintaining radiation equipment. The outcome of the radiation risk assessment and recommendations given by the manufacturer should enable the employer to determine required maintenance and testing schedules.

Controlled areas

What is a controlled area?

A controlled area is one which has been designated by an employer to assist in controlling and restricting radiation exposures. Controlled areas will be designated because the employer has recognised the need for people entering an area to follow special procedures.

Who can enter a controlled area?

Entrance into controlled areas is strictly controlled by the employer. Employees designated as ‘classified persons’ and outside workers can freely enter the area, provided they have been authorised to do so by the employer and have received appropriate training. Other employees should only be allowed conditional access and only in accordance with prior written arrangements.

Dose monitoring

Do I need to monitor staff?

The prior risk assessment you carry out for work with ionising radiation should consider the potential radiation exposures an individual may receive during the course of their work (including accidental exposures). This will help enable you to make an estimate of likely radiation doses and whether staff should be subject to personal dose monitoring. The risk outcome of this assessment will also determine whether certain employees should be designated as classified persons.

Further information can be found in: Radiation doses – assessment and recording.

How do I find a dose monitoring service?

For your workers designated as classified persons, you must employ an approved dosimetry service (ADS) to make assessments of all radiation exposures that are likely to be significant. Dose records for classified persons must be held by an ADS which is specifically approved to keep such records. For information on approved dosimetry services, including a list of HSE-approved services, see the Approved Dosimetry Services webpages

Where an employer provides personal dose monitoring to non-classified workers, this does not have to be carried out by an ADS. However, any employer who makes alternative arrangements for assessing doses to non-classified workers should be able to demonstrate that measurements and assessments have been made to a satisfactory standard.

What is a classified person?

If an employer considers that their employee is likely to receive an annual dose of ionising radiation in excess of three-tenths of any dose limit, they must classify that employee. Classified workers are subject to additional radiation protection measures; their doses are assessed and recorded, and they are also subject to medical surveillance.

Employees can only be classified if they are aged 18 years or over, and if they have been certified as fit for the work by an appointed doctor (or employment medical adviser).

What does it mean to me if I am ‘classified’?

As a classified person your employer is required to inform you that you are classified, assess and record your radiation dose and ensure that you are fit to work with ionising radiation.

I have been issued with a radiation passbook. What does this mean?

If you have been designated as a classified person by your employer, you will be given a radiation passbook if you must enter the controlled area of another employer. Your estimated dose, from each time you have worked in another employer’s controlled area, should be recorded in this passbook.

For further information on outside workers, see: Protection of outside workers against ionising radiation.

Appointed doctors

What is an appointed doctor?

An appointed doctor is a registered medical practitioner who has been appointed in writing by HSE, for the purpose set out in the Ionising Radiations Regulations 1999 (IRR99). The appointed doctor is responsible for checking whether employees are medically fit to work with ionising radiation.

Do I need an appointed doctor?

You will need an appointed doctor or employment medical adviser if your employees are subject to medical surveillance under the Ionising Radiations Regulations 1999.

How can I find an appointed doctor?

For details on how to find an appointed doctor, please see the Appointed doctors webpages.

Smoke detectors

Do the Ionising Radiations Regulations 1999 (IRR99) apply to smoke detectors?

Some smoke detectors (ionising chamber smoke detectors) use a small quantity of radioactive material to determine the presence of smoke in a room.

HSE has issued a type approval certificate for the installation and bulk storage of ionisation chamber smoke detectors. The purpose of the certificate is to relieve employers of the obligation to notify HSE and consult with a radiation protection adviser, where these devices are installed (or less than 500 are stored) and no other work with ionising radiation is carried out.

However, this approval does not exempt employers from any of their other duties under IRR99.

Body scanners

Are ionising radiation body scanners safe?

Body scanners that use ionising radiation should be installed, operated and maintained in a way that does not put the health and safety of passengers and workers at risk. HSE has no evidence that these body scanners are being installed, operated or maintained in any way that poses a risk to health and safety. Further information on body scanning at airports can be obtained from the Department for Transport.

Working alone

Can I work alone with ionising radiation?

There are no specific rules for working alone with ionising radiation, although the hazards and risks associated with lone working should be identified and evaluated in the radiation risk assessment. For general information on working safely alone, please see: Working alone.

Updated 2012-10-15