Radiation Protection Glossary

A radiation protection glossary for Radiation Protection Supervisors (RPS), Radiation Protection Advisers (RPA) and anyone else interesting in radiation safety terms and definitions. The glossary is a mixture of health physics , phrases related to radiation protection legislation, transport, practical safety, technical terms and similar.

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Outside worker

An ‘outside worker’ is term used in the UK Ionising Radiations Regulations 2017 (IRR17).

What is an outside worker?

You will be an outside worker under IRR17 when both of the following apply:

(A) You are a designated classified person or a non-classified person, working for an employer or you are self-employed, and

(B) You are carrying out work (services) in a controlled area under the control of another employer.

Under IRR17 you do not need to be a classified person to be an outside worker (which was the case under the previous IRR99 regulations).


Example (outside worker)

You are a service engineer and you are required to calibrate an x-ray source located in a controlled area of a customer site. Regardless of your classified person status, you will be an outside worker and you, your employer and the employer in charge of the controlled area will have specific duties under IRR17.


Examples (where you are not an outside worker)

You will not be an outside worker when one or more of the following apply:

(A) You enter another employers controlled area only as a visitor (e.g. supervised entry and no practical work takes place)

(B) You are employed by both employers

(C) Where the controlled area is handed over to you (you take charge) so that you are now working in your own employer’s controlled area.

(D) Where you go on to another employer’s site and set up a temporary controlled area

In the above examples: (C) could be an engineer who takes charge of an x-ray room to undertake repair work, and (D) could be a NDT company setting up a temporary controlled area for site radiography.

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