Memories from the past – early radiation protection practice
Published: Dec 30, 2022
It’s 0500 on the 30th December 2022 and I have given up on sleep – I find myself laying in bed and thinking about my health physics (radiation protection) past – not just what I used to do but also thinking about the culture of the time, the tools of the trade and the things we now take for granted (like mobile phones, computers, high tech electronic dosimetry and the like). Mulling over the equipment side of things I was about to conclude that nothing much has changed (many of us use at least one Geiger-Müller based instrument invented in 1908). However, it is not true to say that health physics instrument has not moved on – we use plenty of modern equipment, much of which now uses digital displays, although I still prefer reading an analogue scale.
It started at Amersham International
I was an Environmental Safety Technician (Health Physics Monitor / Surveyor) in the late 80’s at ‘Amersham International’ (now part of GE where the site has closed for commercial operations and is being decommissioned). This is where my real radiation protection career began and I still look back at the period with some fond memories. In fact I never underestimate the impact of real radiation and contamination monitoring at the work face – something I felt that was considered little on a Graduate Health Physics Training Scheme I attended in the mid 90’s with a different employer (having completed a degree at Nottingham University in between). The practical side of health physics has always been important to me and to Ionactive Consulting. I was shocked to hear a fellow graduate trainee say years later ‘monitoring is for the industrial workers, all they need to do is point and record the result’. I hope they are not an RPA for your organisation.....
Radiation Protection Practice
I recall that work at Amersham was undertaken in compliance with the Ionising Radiations Regulations 1985 (IRR85). Therefore the dose limits we were working to at the time were 50mSV effective dose whole body dose (annual legal occupational limit) and 5mSv effective dose to other workers (i.e. the ‘public dose limit’). I cannot recall the company investigation levels at the time but do recall that exposures then were generally higher than I have seen later on in my career.
For example, annual exposures above 1mSv were not considered unusual (compare that now with average occupational exposure in the nuclear industry). Dose sharing was not uncommon; I even recall a massive cyclotron refurbishment job where a significant proportion of the workforce (including those that were not everyday radiation workers) were employed (in a voluntary capacity) to ‘do their bit’ (and taken their proportion of the collective dose for the project). I am not saying this was wrong at the time – however perhaps difficult to justify almost 33 years later where the drive for occupational exposures is ever downwards (despite the concept of ALARP – as low as reasonably practicable – not requiring this at all). It was at this time I came across the term 'gamma fodder'
ALARP was practiced during my early years but the concept in my view was still not embodied in the production process of the time (which is not surprising as many of the processes were using aging plant). The practice of ‘trashing out’ - taking a hot (highly radioactive) package out of a cell and rapidly moving it to a safe shielded container) was not uncommon. Today one would need to show that better engineered means of undertaking this task were not ALARP before allowing this to continue. In fact during my time watching this task take place I often also heard the phrase 'getting your fingers burnt'.
I recall the practice of ‘working up to dose limits’ was still quite prevalent. I noticed this mostly in the engineering sector where critical engineers may have used up their ‘dose budget’ for the month therefore requiring a less suitable engineer to complete the task. This sticks in my mind since as a Health Physics Monitor one of my roles was ‘coverage monitoring’ – i.e. monitoring engineering jobs such as breaking containment into equipment and services. I used to wait and see what engineer would be doing the job – this then dictated the level of real monitoring (and post job decontamination!) required.
Even in those earlier days, when not quite confident enough to question my peers, I often pondered the invisible ‘safety line’ between the engineer who was in a full frogging suit (pressurised air fed suit) and myself and others (supervisors, managers, other engineers etc) who were wearing lab coats.
The above memories are not in any way intended to be critical – it’s just the way things were as I recall during that period of my early career in radiation protection. The important thing is that it taught me a lot about problem solving. At Amersham you had the challenge of working in a potentially aggressive commercial environment, using plant that was producing important medical products, whilst maintaining a level of acceptable heath, safety and environmental performance. In my view it was an excellent introduction to the world of radiation protection.
Computers
I sit here writing this blog on a wireless surface pro 8 – I have mobile (S10) to my left which provides real time emails / communication where ever I am. How so very different it was during those first years in radiation protection.
In the late 80's the286 / 386 Intel computers were available if you looked hard enough – but forget the Radiation Protection Adviser (RPA) of the time sitting in front of his work station and sending off a few well-chosen emails..... How did we manage then? The Telex and Fax were still their tools of the trade at that time. There was no 'windows' and there were no emails !
I do recall seeing a new Colour Photocopier being installed just before I left. It was the size of a small car. Nowadays I can print from my laptop directly to my colour laser printer – which is now the size of an average desk top printer (but still weighs about as much as a small car, and I should know having moved it between offices over the years).
During my time as a Health Physics Monitor all survey reports were hand written and all diagrams were also hand drawn. The funny thing is I am quite sure what was produced was adequate and fit for purpose. I’m equally sure that with all the modern technology we have today there is a temptation to embellish modern day equivalent reports with groovy graphics - just because we can. It might of course take twice as long to complete.... who said modern IT technology was designed to make work more efficient!!
However, computers clearly have made their mark in radiation protection – both as standalone PC’s for running computer codes and as integrated components of modern instrumentation (like using Bluetooth to interrogate a real time active dosimeter). With the internet as you can easily tap in to some fabulous resource like the Rad Pro Calculator and our own Ionactive Radiation Protection Resource hub. We use the latest version of MicroShield – running such shielding calculations from your desktop would have been unheard of during the late 80’s (unless you were able to run ISOSHIELD mainframe code or early Apple 2 or DOS versions). We also have MCNP (Monte Carlo N-Particle Transport CODE) for evaluating more complicated radiation protection solutions.
Modern technology has no doubt improved workflow in many ways. During a critical examination of a linear accelerator facility (e.g. a hospital radiotherapy ), we will use the camera phone to take a 'walk and talk' around the complete facility. This is then uploaded to the cloud in the background and is available by the time we get back to the office. This allows us to then take a virtual tour around the facility and make observations and notes in slow time. Active signs and alarms can be videoed for later playback. Not only is evidence of the examination preserved, but if there is a query regarding our issued report we can go back and have another tour of the facility to recheck our observations.
Communication
We live in the communication age. My two essential gadgets are my mobile (currently an S10, so getting on a bit!) and my Google Maps (app). The mobile tells me where I need to be and who I need to see, whilst Google Maps tells me how to get there. Back at the start of my career mobile phones were unheard off (I use the word ‘mobile’ deliberately since there were phones about which required you to carry the battery on a trolley!).
Those were the days when we communicated by radio at Amersham International – I seem to recall my call sign was ‘TRC 21’ ('The Radiochemical Centre 21' no less). At the time I was at Amersham they had B27 (Cyclotron Building) and B20 (processing building). At various times in the day there would be a requirement for a cyclotron target irradiated in B27 to be moved to B20. This was achieved by use of a stacker truck and specially designed cyclotron target shielded transport cell. Once the target was loaded into the cell the 'stacker' would be called on the radio to collect the cell and transport it down the site road to B20. This is when I would get involved...
- TRC "stacker" to TRC21 - over
- TRC21 to "stacker" - pass your message over
- TRC "stacker to TRC21 - I am moving a target from B27 to B20 and request health physics monitoring, over
- TRC 21 to "stacker" - message received, on my way now and will meet you at the B27 loading doors. OUT.
And so after this exchange I would be armed with various radiation monitors and make my way up to the B27 loading doors. Here I would take dose rates (I think the limit was < 100 micro Sv/h on the surface of the cell) and smear (wipe) to probe monitoring (to demonstrate absence of loose radioactive contamination).
Good memories, and some many years - err - decades ago!
Mark Ramsay, Ionactive Consulting Limited, 31 December 2022.