Blog 2024

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? 

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 ...

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!

A short set of articles introducing new Ionactive radiation protection training resource as widgets. The widgets are small interactive teaching aides that will feature on our public website and also extensively in our on line radiation protection training service. First up is the inverse square law.

A few blog posts back we discussed radiation accidents in industrial radiography. We provided examples where immediate action was required to prevent or reduce exposures to ionising radiation. Where a radiation accident is reasonably foreseeable, IRR17 requires contingency plans to be available and rehearsed. There seems to be an expectation by many employers (and regulators) that local rules will always have contingency plans (or a reference to them). The potential for a radiation accident is determined by your radiation risk assessment. Are radiation users providing contingency plans regardless of the risk, and the definition of a radiation accident? Let's discuss.

Drop and run (from a radioactive Co-60 source) has featured in a number of blogs and articles over the years, and more recently in some online videos from content creators. From a shock perspective many of these paint a pretty grim picture (and this is not without merit). However, third or 4th hand information tends to muddy the waters and inaccuracy creeps in. This article provides some radiation safety data and comment on the principles of drop and run, and in particular some analysis of the infamous Co-60 source picture which has found itself onto t-shirts and cushions!