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17/2/2011 - Radiological Dispersal Device (Dirty Bomb) notes for Media and Public (1 of 4)

Ionactive RDD Dirty Bonb Resource 01

Have given this some real thought before writing this blog entry. It is certainly not aimed at the would be terrorist - so I had to think about giving away specific information that might be used maliciously. I conclude that the average terrorist aiming to cause havoc by this method would neither be thick or unaware (in terms of what to do) - it is all over the internet. So it's not for them, but if they do read it then they may be a little disappointed.

The blog is written mainly for interested media parties, and other folks with a genuine interest in the "Dirty Bomb", or as the ‘professionals' will call it, the Radiological Dispersal Device (RDD). The more scientific term is rather interesting because it expresses the intent of the device to ‘disperse' - and this you will see is rather difficult to do well. If you do sort out your dispersal then by default you also dilute (in the sense of spreading activity over a wide area, in the wind and so on).

I am writing this because 'Dirty Bomb' is back in the media again, almost entirely as a result of wikileaks - such as this story :' Al Qaeda actively seeking "dirty" bombs: documents '. There are many things amiss with that article - or at least are assumed or taken for granted. The first is the use of the phrase ‘nuclear material'. We shall look at this in more detail in a moment, but let us be clear that nuclear material, as correctly defined, is a poor choice for a dirty bomb (indeed it is a waste of a terrorists precious resource!). Secondly, the article seems to suggest that such a device is ‘built' - well it is (sort of), but the suggestion is that it needs ‘brains'. A dirty bomb is no more than radioactive material and explosive combined - this is about as far removed from a ‘nuclear device' that you can get. If the dirty bomb is being able to crawl up a flight of stairs, the nuclear device is crawling up Mount Everest, blindfolded, hands tied behind back, in a storm...

Starting with a conclusion. For those not willing to read to the end, the RDD is a MAD device - that is, it may cause Massive Assured Disruption (borrowing and tweaking an old Cold War term). This is my own personal opinion, and some of my peers disagree (following various forum discussions). Most disagree because they will say that the likely radiation exposures to members of the public or emergency services will be low - this is based on their knowledge of radiation protection. I do not disagree with their knowledge, or their health physics based conclusions and dose assessments, rather I think many are missing the point. The RDD (Dirty Bomb), if one is ever made and used, is a basic and very crude terror weapon. Terror is the key word here - you only have to follow WWW threads on potential new Nuclear Power Station build to see how many view ‘radiation' - and this is the key - radiation still frightens many.

Take a look at the Nuclear page on Greenpeace. I am not knocking them, they do what they do for their own reasons and belief.

However I would add, for the benefit of the public (who might be worried), any radiation hazard produced from such a device would be dealt with by a very capable team of experts (but perhaps not according to Greanpeace!). OK, in the early hours of an event it will be first responders (the emergency services), but it will not take long for the nuclear industry veterans to get involved and sort it out.

This blog entry does not attempt to evaluate radiation exposure rigorously. Others have done this, but most of this is used by consultants with complicated computer models, attached to city models, attached to metrological models etc. No, all I will do here, when discussing exposure, is to provide an order of magnitude ("about") figure for potential exposure. So in this blog entry I will discuss.

1) External Hazard vs Internal Hazard
2) Some likely sources (and why most are no good)
3) The device - dispersion vs fragmentation
4) Exposure potential & risk

External Hazard vs Internal Hazard

As I have already noted, the purpose of the RDD is to disperse material. This is important because this is different from a common misconception of ‘dispersing radiation'. It is the physical mass of radioactive material that is dispersed, and if dispersal is complete and wide reaching then this effectively becomes a massive number of smaller and smaller ‘sources'. This then brings us on to the concepts of External Radiation Hazard (or exposure) and the Internal Radiation Hazard (or exposure). We need to understand these clearly since this will define how a person is exposed and therefore their likely radiation dose should they unfortunately be near a ‘dirty bomb' event.

Ionactive Training External Radiation Hazard 

The picture depicts an external radiation hazard. Note that the source of the radiation (in this case gamma rays) remains firmly fixed outside the body - the material is not moving - indeed the person exposed could get up and walk away (they would not be contaminated). For a dirty bomb (RDD) the worse case dose rate, that is the rate at which you would receive an external radiation dose should you be near it, would be right next to it - sitting on it perhaps! The actual dose rate would depend on the type of radioactive material, its emissions, its activity and indeed if the RDD device had some sort of shielding employed (perhaps to make it more difficult to detect whilst being moved around). It is also fair to add that some radioactive materials - such as tritium (a very poor choice for a RDD but highly dispersible in certain forms) would yield no dose rate at all (due to its very low energy beta emissions). Your actual dose in the above example would also of course depend how long you were sitting on top of the device! Now consider the following picture.

Ionactive Training Internal Radiation Exposure

The second picture now depicts an internal radiation hazard. Note now how the radioactive material (the source) has been broken up into many tiny pieces (dispersed) and each of these tiny fragments may move around. The picture shows, in general terms, that the radioactive material may be taken in by inhalation, ingestion or adsorption through the skin (or through an open wound). The actual intake of material is affected by a vast range of variables which could include:

  • Physical particle size of the material (not the radiation!)
  • The chemical nature of the material (not the radiation!)
  • Environmental factors (wind, rain)
  • Where you are in relation to this moveable radiation
  • What you are doing (breathing, ingesting, walking, running, using breathing protection)
  • Overall concentration of active material in your environment

What makes exposure predictions difficult is that many of the above factors can be changing rapidly over time. However, what is important to note and which will be explored in further detail below, is that the more prefect the dispersion into the environment (call it perfect mixing in the environment), the lower the activity concentration at a specific point in that environment. In turn, the lower the concentration of radioactive material (not radiation!), the lower will be the exposure for a specific critical person. Of course, the actual exposure of a critical person will depend on what they are doing as has already been suggested (e.g. the longer they stay in an area breathing air contaminated with radioactive material, the higher their potential dose might be).

However, even then, ‘intake' of that material does not immediately suggest a massive radiation dose is certain - this would depend on the total activity taken in (per minute, per hour, per breath, per hour you stay in a certain contaminated area etc etc), and also the chemical and physical nature of the radioactive material. It would be further influenced by the wind, rain and other environmental factors. Furthermore, the choice of radioactive material (its radiation properties) would also influence the dose received.

However, in the final analysis, the more perfect is the dispersion of radioactive material, the less the potential exposure will be to a certain person at a certain location at a certain time for a certain duration. Take a look at this small video below (no audio) - it presents a nice summary of the above discussion.

What we can conclude at this point in basic terms and with some assumptions, is that the closer you are to the device (the dirty bomb / RDD), the higher will be the potential radiation exposure. Before the device detonates, the dose will be dominated by the external hazard, after it detonates the exposure will be dominated by both (but the internal hazard will only dominate if dispersion is highly efficient). However, the closer you are to the device when it goes off, the more likely you are to be injured by the blast - and I am quite certain that blast injury (if you survive) will dominate (the radiation risk / damage / exposure) will be insignificant.

The further you are from the point of detonation, the less likely you are to be injured (by flying debris etc) and the less likely you are to be concerned with radiation exposure. If dispersion is less than perfect then the radiation risks to the public and services outside the confines of obvious explosive damage will be even less still.

Part 2 to follow soon.

14/2/2011 - Lamb Cobalti-60 a curry with a 'radioactive' twist

Ionactive Training Resource - Co-60

OK, so it is not radioactive (of course), but I always like to combine my interests together. Put it this way, my wife asked that the kitchen be decontaminated after cooking this, so that pleases me no end (must have been good!).

Unlike my recent cooking exploits (e.g. cooking lamb madras takeaway style), this curry is quite quick to prepare and cook. It is far removed from the takeaway style, but I suspect much more like the kind of thing to be found in the home of traditional Asian cooks. I have used lamb for this curry and did try this using ‘meat on the bone' (knuckle joints), but to be honest I prefer this with ‘neck of lamb'. Neck of lamb can be a bit fatty, so do not eat too often, but the taste and texture is fantastic!!

The only real bit of ‘prepared before' that you need in this curry is ‘mixed powder' - this was created in my lamb takeaway blog - I have copied that part into the bottom of this blog entry again - it only takes a few minutes to prepare. Anyway, this is what you do to create Lamb Cobalti-60.

Lamb Cobalti - the spices

Take a plastic box, big enough to accommodate enough lamb (I made this just for me - as you might have expected ...). Then put the following in:

  • 1 Tablespoon of the Mixed Powder
  • 1 Tablespoon of crushed Garlic
  • ½ Tablespoon of grated Ginger
  • 1 Tablespoon of chopped Coriander leaves
  • ½ teaspoon of black mustard seeds
  • Four green Cardamom pods (important do not crush)
  • 1 Tablespoon of chopped Chilli (adjust the ‘activity' to your liking)
  • 1 Tablespoon vegetable oil.

Mix that lot together, then add the lamb. Cover and mix around (shake etc) and then leave in the fridge for as long as you can (at least an hour).

Lamb Cobalti - lots of nice red onion!

Then fry off some red onions in a pan. When your seasoned meat is ready, add to the onions and stir around until sealed.

Lamb Cobalti - other ingredients

Than had some chopped mushrooms (handful should do). Then add one small tin of plum tomatoes, breaking them up with a spoon as you mix them in. Add some water and then cover and simmer until the lamb is cooked (adjust the water during this process). I cook the lamb for about 1.5 hours. During this cooking process the cardamom pods will bloat up - remove them if you wish (I like to leave them in, like the kick they give when you bite in to them).

You will notice above that I have also added some whole chilli as well - gives a nice kick when you bite in, leave out if you wish!

Lamb Cobalti cooking (minus the tomato at this stage)

Towards the end you can add some chopped pepper if you wish - the curry is then ready when these have softened.

Then you have the Lamb Cobalti-60, ready to eat!

Lamb Cobalti 60 - complete and ready to eat!


(Here is how to make the Mixed Powder again)

The Powder Mix

For this we need the following - all should be in powered form and needs no pre-cooking / heating. You simply mix the proportions in an air-tight container - that is it.

2 tbs Curry Powder (any medium curry powder will do)
1 tbs Cumin Powder
2 tbs Coriander Powder
2 tbs Paprika Powder
3 tbs Turmeric Powder
1 tbs Garam Masala

Powder Mix

The Powder mix ready to go

24/1/2011 - Radiation Protection in the Gulf

Ionactive in Bahrain - Palm

Well the radiation safety training in Bahrain is almost over. I am really looking forward to seeing my wife and boys - working in Bahrain has been an excellent experience and I have made many acquaintances, but seeing my family is something I am really looking forward too!

Day 3 of the course number 2 commences on Tuesday morning. You know .. I love training and meeting people but I can honestly say I feel exhausted at this point. Running two bespoke courses back to back is not easy and being away from the UK awful winter weather has certainly not been a jolly (something some of my friends and colleagues have teased me about).

The material has not been particularly difficult to deliver, and the delegate interaction has been excellent, but the process of course delivery over the last 10 days is not a walk in the park. That said, I am of course looking at the opportunities for delivering further courses to this region in the near future.

I have tonight been asked to put a proposal together for radiation training in the Ukraine .. of course a very different area but the experience of working around the damaged reactor is not to be missed.

Returning to the people in Bahrain, or those I have met in Bahrain from other regions in the Gulf, they have really made this experience worthwhile for me. During the first course I shared the car everyday with Mahmood AL Jadeedi, a delegate from Oman who was staying at my hotel. He was excellent company and I hope to meet him again sometime in the future.

Ionactive Delegate from Oman

Here is a selection of delegates from the first course run in Bahrain.

Ionactive Bahrain - First Radiation Safety Course Delegates

22/1/2011 - Radiation Safety Training in Bahrain

Ionactive - providing Radiation Safety to Oil and Gas Industry in bahrain

Well we made it. This work had been planned for some time and we arrived on the 17th of January to deliver two 3 day radiation protection courses to the Oil & Gas industry in the Kingdom of Bahrain. This work was commissioned after a Health and Safety expert from the company in Bahrain had attended our routine 2 day RPS course in the UK (see Ionactive Radiation Protection Supervisor Training Courses).

We are training initially 20 delegates from various areas of the company including health and safety, safety systems management, environmental management, contractor control, quality assurance etc.

Ionactive Radiation Protection Training - beyond the UK

As mentioned in earlier blogs we have seen a steady increase in delegates from all around the world attending our courses in the UK. We believe this is for two reasons:

1) The delegates (typically from Bahrain, Qatar, Oman, Ukraine, Angola, Mexico etc) recognise best practice in radiation protection in the UK, and the robustness of the UK legislative framework (i.e. the Ionising Radiation Regulations 1999).

2) Ionactive radiation protection training courses have been shown to deliver excellent value for money, are innovative and have consistently had excellent feedback. (To be fair we have also had some excellent constructive criticism over the years too which has enabled continuous improvement).

Ionactive Radiation Safety Training in Bahrain

In being invited to Bahrain we were given the remit of delivering a bespoke radiation safety course that was of the standard of a Radiation Protection Supervisor (RPS) course as recognised in the UK. In addition to this base line remit, we were asked to ensure that three specific matters were addressed during the three days of training. These were:

a) NORM (Naturally Occurring Radioactive Material). Our course explains the origin of NORM and the production of TENORM (i.e. Technically Enhanced NORM). The course looks at NORM with specific reference to the oil / gas industry - dealing with locations and form, activity concentrations, protection methods, monitoring, personal protective equipment etc.

b) Industrial Radiography. However you look at it, there are still accidents occurring in NDT (Non Destructive Testing) which utilise radioactive sources or x-ray generators. Indeed, we have featured a number of incidents in this blog including a severe overexposure which occurred in Poland during 2010. Many companies, including the oil / gas industry, will employ contractors / sub-contractors who will undertake NDT. The aim of our course is to clearly explain the risks and issues, and highlight how an audit should be undertaken to pick the right NDT contractor for the task required.

c) Nucleonic gauges. We work with a number of companies who produce, install and use nucleonic gauges in the oil / gas industry. A popular component in oil flow measurement is the Multi-Phase Flow Gauge (MPFG) which normally uses a radioactive source (such as Cs-137). The courses looks at all the radiation protection aspects of using such gauges as well as other forms of measurement (e.g. tank level).

IAEA 115 and IRR99 set the standard

Arabic IAEA Safety Series 115 (Radiation Protection)

The course recognises that whilst most counties in the world now belong to IAEA (International Atomic Energy Agency), not all yet have a fully developed legislative framework for radiation protection and regulator oversight. In this regard the course is fully compatible with the IAEA Safety Series 115 (International Basic Safety Standards for the Protection against Ionising Radiation and for the Safety of Radiation Sources) and the revised system that is currently being developed by IAEA. Since the UK Ionising Radiation Regulations 1999 (IRR99) regulations are a descendent of IAEA (via European Directives), they are an ideal platform to use in training around the world - as we have found during our courses in Bahrain.

Indeed it is understood that local radiation protection legislation is being examined by the parliament here right now and new laws will perhaps be in place during 2011 or 2012.

In this region there appears to be a variation in attainment of local legislation with respect to radiation protection. For example, Oman has had a system of regulation for some years, whereas Qatar put a system in place during 2002 with the following law: The Executive Regulations of the Decree-Law No. (31) of the Year 2002 Concerning Radiation Protection. These were largely based on the IAEA safety series mentioned above, particularly with respect to licensing. For example in Qatar a Site License is granted: after the planning stage of ionising radiation use is deemed adequate by the regulator. An Installation License is then granted: after the installation of plant and protective features for ionising radiation use have been deemed adequate.

The Qatar legislation also appears to have borrowed bits from the UK IRR99. This is mainly a good thing (!) but I present a word of caution here. Whilst the UK system does encourage best practice I do not think the range of legislation and regulators is a particular model that I would encourage regardless of the physical size of the area being regulated (e.g. comparing the UK and Bahrain).

In the UK we have the Ionising Radiations Regulations 1999 (safety), the Environmental Permitting (England & Wales) Regulations 2010 (environment), the Radioactive Substances Act 1993 in Scotland (environment), the Ionising (Medical Exposures) Regulations 2000 (medical) etc. To compliment this we are regulated by the Health and Safety Executive (HSE), the Environment Agency (EA), the Scottish Environmental Protection Agency in Scotland (SEPA), the Department for Transport, and Office for Civil Nuclear Security (OCNS) etc. I am sure if all this was starting from scratch then a simplification would be in order. So Bahrain - please take note! Anyway I digress.

Bespoke Ionactive Radiation Protection Course Material

For this training course we produced bespoke colour training manuals which were shipped over ahead of the training. The course material is also available in PDF form but we favour training from real documents in the first instance. The training is a mixture of formal presentations, delegate discussions, table top exercises and tests. On successful completion of the tests the delegates will be awarded an ‘RPS Achievement Certificate' which carries the Radiation Protection Adviser (RPA) certification number as recognition of a quality standard.

We have been using a range of video animations as well to complement the training (some of these are available on the Ionactive YouTube channel). Of particular interest has been one of our more recent offerings looking at the advantages of Enclosure Radiography. This was designed to demonstrate best practice in industrial radiography - it is recognised however that most industrial radiography out in the open oil and gas fields needs to be ‘site' based. That said, by instilling in the minds of the delegates the safety features offered by enclosure radiography, the extra care and attention needed for field based site radiography becomes more obvious. Take a look at the enclosure radiography resource below.

A number of exercises are offered on this course - including incidents involving radioactive sources and NORM. The differences of working with NORM and sealed radioactive sources are made very apparent, as is the relative risks of External Hazards vs Internal Hazards. Furthermore the ability to adequately monitor (or otherwise) is also explored. For example, monitoring external radiation dose rates from an exposed Ir-192 source is relatively easy; the same cannot be said for monitoring alpha contamination from suspected Po-210 in oil / gas separators (for example).

We have spent some time looking at the Uranium and Thorium decay series and examining secular equilibrium and then the Technical Enhancement (TE) which leads to these decay chains becoming disrupted. Case studies from the Ceramic Industry (another area which needs to concede it has NORM issues) are also used to illustrate these processes. For example, the high temperature processing of feedstock containing NORM at low concentrations (e.g. Zircon Sand), can lead to unchecked levels of Pb-210 and Po-210 in gas scrubbers / particulate filter systems. Whereas the Pb-210 / Po-210 in the feedstock will be substantially less then 0.1Bq/g, we have seen concentrations easily approaching 50-100 Bq/g Po-210 (this being within a fine respirable dust). Therefore dealing with NORM issues, either during routine maintenance or during incidents, is complementary across the industries (i.e. oil / gas / ceramics / steel making / pigment production etc).

The interaction between delegates and their engagement in the course has been most welcome - this is really appreciated as it makes the life of the trainer that bit easier.

Mark Ramsay in Bahrain

Mark Ramsay at the  Almoayyed Tower

Whilst most of this trip is about work we have had the opportunity to take a look around. Preparation of this course has been intense and more so given a bout of recent sickness of the RPA Mark Ramsay. In addition the work of the consultancy has to continue so we are catching up on several projects with more to get involved with when back to the UK. It's actually a hectic end to this week once we are back midweek, with x-ray / Kr-85 training on Thursday, a trip to Cornwall and back on Friday (more NORM!) and then Birmingham on Saturday for a critical examination of a new linear accelerator facility. We were involved in the design of the 10 MeV radiotherapy bunker and its critical examination is always a time of slight nervousness!

Anyway our host took us on a trip around some parts of Bahrain including the oil fields. It is currently ‘camping time' at the moment - something I confess to not really know the origin off. It is quite a sight to see tents, and in some cases some quite elaborate (and not so elaborate) ‘camps'. These are all mingled within the oil fields, with pipes crisscrossing in between some of them. Oil wells can be seen all around with the signature flares being evident in the background.

Breaking off mid flow - just hearing the call to prayer whilst I am writing this - amazing fulfilling sound indeed.

Bahrain Fort (Qal`at al-Bahrain)

We also took a trip to see the Bahrain Fort - this trip included an unintentional de-tour (before we employed the sat-nav). This de-tour took us down some back streets away from the main city and that was an eye-opener.

Mark Ramsay in Bahrain - a different side of Bahrain

It is true that the UK has people and homes with very mixed fortunes, but somehow the stark difference between those with much, and perhaps not so much, is more obvious in such a compact country.

What I can say is that everyone I have met: from delegates, to managers, to hotel staff, to drivers etc - has been very friendly and welcoming. Regardless of fortunes everyone appears to do their work with a level of pride that is, in my opinion not always displayed by some within the UK.

I am not saying this is right or wrong, or justified or even real (I do not know) - it is just an observation from my short time here. I needed to ask directions from a chap who was sweeping a street earlier today, he spoke excellent English and could not have been more helpful - I am sure if he had been allowed he would have stopped what he was doing and taken me on a tour!

Well that is all for now. Preparing for some UK Fire Service RPS training the week after next.

9/1/2011 - Overexposure of a field radiography worker

This is taken from the IAEA event log.

Overexposure of a field radiography worker (Republic of Korea)

What follows are two reports which were filed on the 5/01/2011, but which relate to two incidents - 4 November 2008 and 3 March 2009. Not sure why this took so long to get onto the system.


On November 4, 2008, two field radiography workers took overexposure incidentally with radiography equipment containing 1.8Tbq (47.7Ci) Ir-192 sources at pipe welding workshop located in Yeosu province southern part of Korean Peninsula.

The incident caused from returning the disconnected pig-tail source to the source container by those of two workers without any preventive or protective measures. The investigation unfolded that any survey meter was not deployed to working place and an alarm meter worn by one of worker was not properly working. They could not realize dislocated pig-tail source till loading the source container on the vehicle due to the absence of any detector.

The received doses of the two workers were estimated as approximately 51 mSv and 62 mSv, respectively and this event was rated as level 2 on the INES scale.

A field of radiography worker took overexposure incidentally with radiography equipment containing 2.1TBq (55.8Ci) Ir-192 source at the pipe welding workshop located in Jinju southern part of Korean Peninsula, on March 3, 2009.

The incident caused from the wrong direction of crank handle by radiographer's confusion. The investigation unfolded that any survey meter was not deployed to working place and the worker did not wear a personal dosimeter as well as an alarm meter. The absence of any detector made cognitive failure of worker that the pig-tail of Ir-192 source was still being outside.

The radiography worker burned severely on his fingers and the extremity dose and whole body dose were estimated as being about 50 Gy and 200 mSv, respectively. This event was rated as level 3 on the INES scale.

The incident log for the above two events can be read at the following link: IAEA News (You may need to log in as a guest).

Ionactive Comment

Well, the same things keep cropping up again and again.

  • Lack of radiation protection training
  • Lack of use of suitable radiation monitors
  • Inadequate training in the use of the equipment

In both cases a substantial whole body effective dose of radiation was received - in excess of the legal limit. In the second later incident the individual received an equivalent dose to the fingers of around 50Gy (the threshold for deterministic effects to the skin is about 3Gy).

There appears to be a complete lack of awareness with respect to the radiation hazards present - no concept of time, distance or shielding is evident. The fact that monitors were not deployed or working, nor dosimetry, is simply deplorable. It is annoying that these over exposures are so easily preventable with just basic awareness and proper use of radiation detectors.

Notice also how these incidents, and other similar ones reported on this blog, are during ‘open site' radiography conditions. Open site radiography should never be considered the default position, wherever possible the item to be radiographed should be moved to a dedicate enclosure - perhaps like the one described below.

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This is the company blog of Ionactive Consulting Limited, a Radiation Protection Adviser consultancy. Visit here often to read our views on radiation protection and related matters. You can contact our director and RPA directly at

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