Ionactive Radiation Protection Blog

Our radiation protection blog is predominately written by Mark Ramsay, Radiation Protection Adviser (RPA) for Ionactive Consulting. It contains a mixture of content including day to day descriptions of RPA work, advice and comment on current radiation protection issues, comment on regulator (HSE etc) inspections (suitably sanitised),  historic content (i.e. the Co-60 drop and run story, Alexander Litvinenko Po-210, Fukushima nuclear accident, industrial radiography accidents), radiation safety legislation updates and practical radiation protection in the workplace.  

For formal radiation safety advice. please see our Radiation Protection Adviser (RPA) service pages. 

  • I need a Radiation Protection Adviser (RPA) and Supervisor (RPS) 24/7! Do I really need this?

    Published: Apr 26, 2025

      Tags:
    • RPA
    • RPS
    • Radiation Protection Adviser
    • Radiation Protection Supervisor
    • Suitably Qualified & Experienced Persons
    • SQEP
    • Nuclear licensed sites
    • HSE
    • IRR17
    • Ionising Radiations Regulations 2017
    • Contingency plan
    • Contingency arrangements
    • Radiation Risk Assessment
    • chromosomal aberration analysis
    • CAA
    • Radioactive source
    • Local Rules
    • Dose investigation level
    • Radiation accident
    • Radiation incident
    • Controlled Area
    • REPPIR
    • RIDDOR

    In the UK a Radiation Protection Adviser (RPA) appointment is usually required for work involving ionising radiation (Ionising Radiations Regulations 2017 - IRR17).  Where a designated area is declared (e.g Controlled Area), the employer will need local rules - and this requires the appointment of a Radiation Protection Supervisor (RPS). What should the availability of the RPA  / RPS be for a particular use of ionising radiation? 24/7, or as needed (or as written into a contract, job description or appointment letter)? Let's explore this further. 

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  • X-ray Industrial radiography cabinet vs X-ray radiography cabinet which you can (or cannot) enter – is there a difference, and does it matter? / Are you undertaking industrial radiography (NDT), radiography, x-ray inspection or something else?

    Published: Mar 01, 2025

      Tags:
    • Industrial Radiography
    • HSE
    • Registration
    • Consent
    • NDT
    • Non Destructive Testing (NDT)
    • Radiography cabinet
    • X-ray cabinet
    • X-ray inspection
    • IRR17
    • Ionising Radiations Regulations 2017

    This article is somewhat in two parts. We consider some recent updates from the UK HSE interpretations on what ‘a person being able to enter a radiography cabinet’ means. They have provided some useful information on a number of x-ray cabinet systems that have been reviewed, and whether they consider can be reasonably entered by a person. They have specified if a registration or consent is required (based on ability to enter)  - which appears to suggest that the cabinets are used for industrial radiography. What if you are not undertaking industrial radiography (NDT – non-destructive testing), but instead using the very same cabinet to x-ray a museum specimen,  visualising the internal structure and acquire knowledge about it’s origin, state, or composition?

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  • X-ray cabinet sterilisation (irradiation) – UK registration or consent (IRR17)?

    Published: Feb 23, 2025

      Tags:
    • X-ray
    • Sterilisation
    • Industrial Irradiation
    • HSE
    • Registration
    • Consent
    • Safety Assessment
    • radiation generators
    • Ionising Radiations Regulations 2017
    • IRR17
    • Radiation Risk Assessment
    • X-ray dose rate widget
    • IRR17 graded approach

    You have decided on the make and model of your new laboratory X-ray sterilisation unit. No radioactive HASS sources to worry about, no environmental permit and no security arrangements. You are about to apply for a 'radiation generator registration' from the UK HSE - until you are told otherwise (by the HSE, your RPA or your equipment supplier). You are told you need a consent for industrial irradiation. You are told you need to complete a safety assessment, prepare for an HSE inspection and pay a fee (significantly more than for a registration). For a desktop x-ray unit.? Let's discuss! 

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  • A dose rate of 1 micro Sv/h. A magic line or a bit of a nonsense?

    Published: Aug 26, 2024

      Tags:
    • X-ray cabinet
    • <1 micro Sv/h at 10 cm
    • < 1 μSv/h
    • ALARP
    • Ionising Radiation
    • Ionising Radiations Regulations 2017
    • IRR17
    • IRR17 - Schedule 1
    • IRR17 notification
    • IRR17 registration
    • IRR17 Consent
    • radiation generators
    • Critical examination
    • Ambient dose equivalent
    • equivalent dose
    • effective dose
    • Whole body exposure
    • Dose Rate
    • Instantaneous dose rate (IDR)
    • X-ray emission limit
    • X-ray emission leakage
    • COUNCIL DIRECTIVE 2013/59/EURATOM
    • Dose Limits
    • IAEA - GSR Part 3 Radiation Protection and Safety of Radiation Sources
    • IAEA
    • ICRP 103
    • Exemption
    • Type Approved
    • Type Approval
    • US Cabinet x-ray systems
    • 21CFR1020.40

    Where does the magic < 1 micro Sv/h at 10cm from a surface come from with respect to critical examinations of x-ray cabinet equipment? Why does Schedule 1 of the Ionising Radiations Regulations 2017 (IRR17) contain an apparent exemption for a notification for certain x-ray devices - but all such devices need at least a registration (or consent in certain cases)? What is the 1 micro Sv/h a measure off - equivalent dose, effective dose or perhaps both? Is this value instantaneous dose rate (IDR) or can it be measured and specified as a time averaged value?  Is the < 1 micro Sv/h a de facto legal limit and what are the repercussions of exceeding it? These and other related questions are pondered in this blog - is < 1 micro Sv/h a magic line in the sand? [Updated 19 May 2025 with an interactive radiation  protection widget to test out some of the matters discussed].

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  • My "Hot" delegate

    Published: Jul 28, 2024

      Tags:
    • RPS Training
    • Nuclear Medicine
    • Protection by time
    • Protection by distance
    • Protection by shielding
    • Dynamic risk assessment
    • Expect the unexpected
    • I-131
    • Iodine-131
    • External Exposure
    • Contamination
    • Inverse square law
    • Radioactive delegate
    • Radioactive trainee

    Expect the unexpected. Never assume!  Mark Ramsay, Radiation Protection Adviser (RPA) with Ionactive, looks back at a rather interesting two day Radiation Protection Supervisor (RPS) training course. One of the delegates / trainee (X) brought much more to the course then just experience and enthusiasm. In many ways they become a significant course provider ...

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  • IRR17 - Formal investigation levels (where you don't measure personal exposure with dosimetry)

    Published: Apr 16, 2024

      Tags:
    • IRR17
    • Ionising Radiations Regulations 2017
    • Formal investigation level
    • Dose investigation level
    • Radiation Risk Assessment
    • Dosimetry
    • HSE
    • Health and Safety Executive (HSE)
    • Ionising radiation regulator
    • Instantaneous dose rate (IDR)
    • Accumulated dose
    • X-ray unit
    • X-ray food industry
    • Tritium

    Knowing (and admitting) you are wrong about something is professional - but it is still often difficult to do. This latest blog article is partly about such a case where we wrote in some local rules that a dose investigation level was not formally required. This was wrong and a regulator picked up on this, stating it was a requirement of IRR17. We were not correct with our wording - a formal investigation level in terms of a dose which had been 'pre-assessed' in the risk assessment, and was further verified by regular dose rate monitoring (to show the pre-assessment was still valid), was not considered a formal dose investigation level.  Anyway, a formal dose investigation level was placed in the local rules and we are all happy.

    Well not quite. In IRR17 - 9(8) 'investigations', the limit specifically relates to 'effective dose of ionising radiation ' (whole body dose). In our featured example, assessed whole body dose for routine work and reasonably foreseeable accidents was no greater than background. No dosimetry was being worn (or needed). In our view the practical method of how you demonstrate if a formal investigation level is exceeded (via dose rate monitoring and pre-risk assessment) was more important (and useful) than simply stating the formal investigation level based on an effective dose. Why were there local rules anyway (?) - because our regulator has stated that all cabinet x-ray systems contain controlled areas, regardless of the output of a risk assessment (which might suggest otherwise).

    So, read on!

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If you start from nothing, it is very difficult to get anywhere

– Gerhard Herzberg -