The ICRP have issued a draft report "Early and late effects of radiation in normal tissues and organs: threshold doses for tissue reactions and other non-cancer effects of radiation in a radiation protection context" which is now available for public consultation. A copy of the document can be downloaded via the link below:
The report includes a summary of new evidence for development of lens opacities which is based on the following data:
These new data, together with animal models, show that lens opacities occur at doses <1 Gy. Evidence for lower thresholds has been emerging in recent years from more sophisticated methods of scoring damage, longer follow up (incidence increases with latency), and more data in the low dose region. This information leads the ICRP task group publishing the report to believe that the threshold for protracted exposure is around 0.5 Gy. The draft report contains a proposal for the dose limit for occupational exposure to the lens of the eye to be reduced to 20mSv/y (from 150mSv/y). The draft ICRP report will be on their website for 90 day consultation with a deadline for comments of 1 April 2011.
This is a significant reduction in the proposed dose limit for the lens of the eye and may well have implications not only for the medical sector but also for the nuclear industry (for example glove box, maintenance, or decommissioning workers). It would be wise for duty holders to gather relevant data in relation to their work liable to give rise to significant exposure of the lens of the eye. It is noteworthy that such a dose limit is liable to be included not only in the IAEA Basic Safety Standards Requirements level document but also the draft Euratom Basic Safety Standards Directive.
New occupational health and safety regulations on the management of optical radiation exposure risks in workplaces came into force on 27 April 2010. These regulations and HSE guidance are available on its web site here: Non-ionising radiation - Optical radiation.
The Control of Artificial Optical Radiation at Work Regulations 2010 essentially require employers to review risk assessments that should have been made under the Management of Health and Safety at Work Regulations 1999 if artificial optical radiation exposure risks, arising from or likely to arise as a result of their work, could cause reasonably foreseeable risks of adverse health effects: for example effects such as, skin erythema and burn; photokeratitis and cataractogenesis; retinal burn and photoretinitis, and skin cancer. The purpose is to get employers to develop an action plan for mitigation of such risks so that applicable exposure limits are not exceeded.
Advice on optical radiation sources and applications that may well be capable of causing adverse health effects and those that typically do not, is given in the following HSE guidance Guidance for Employers on the Control of Artificial Optical Radiation at Work Regulations (AOR) 2010.
Employers who are unable to come to a conclusion about the adverse health effect risks their work might cause, will need to seek advice from a competent person, for example a consultant or a lamp or luminaire manufacturer, or carry out or commission their own measurements or calculations of optical radiation exposure arising from the equipment that they use. But in this regard, measurement and calculation should be seen as a last resort in health and safety management rather than something that needs to be done routinely by employers, moreover, the data that such assessments yield should be provided in the first instance by manufacturers and suppliers of work equipment in discharge of their obligations under Section 6 of the Health and Safety at Work etc. Act 1974. If an employer is unhappy about the information provided by their supplier, HSE should be contacted.
On 6 December 2010, Schlumberger Oilfield UK plc was fined a record £300,000 at Aberdeen Sheriff Court for a breach of Section 3(1) of the Health and Safety at Work etc Act 1974 as a result of an incident that occurred during offshore logging operations on the Ensco 101 north-sea drilling rig on 4 April 2008.
A worker from Schlumberger failed to correctly load a high activity caesium-137 radioactive source into a logging tool from a transport container and the source lay unnoticed on the drill floor for approximately four to five hours before being found. During this time fourteen workers from different employers had accessed the drill floor and were placed at risk of radiation exposure. Had someone held the source, even just for a few minutes, they would have received a significant radiation dose which may have resulted in injuries to their hands and increased their risk of developing cancer in later life.
The investigation by HSE found significant failings in Schlumberger's health and safety management system, which included inadequate risk assessment, and insufficient instruction and training for workers involved in logging operations. Of note is the fact that no procedure was in place that required a worker to confirm with a radiation monitoring instrument that the source had been correctly loaded into the logging tool.
The incident was entirely foreseeable and preventable: the possibility of a worker failing to correctly load a radioactive source from a transport container into a logging tool had not been identified in the company's risk assessment and adequate control measures were therefore not in place to control this risk. Confirmatory monitoring after movement and relocation should be fundamental elements of any safe system of work: radioactive source location should never be assumed but rather confirmed. Too many incidents of this nature occur when users fail to identify the importance of this task.
This case should serve to remind employers and employees, whether in industry, medicine or research, of the importance of suitable and sufficient risk assessments and the need to be constantly vigilant when working with radioactive sources.
OTHEA is the name of a new website, created by the Health Protection Agency (UK) and the Centre d'étude sur l'évaluation de la protection dans le domaine nucléaire (CEPN, France). It is also supported by national radiation protection societies and associations, regulatory authorities and other stakeholders.
The website is bi-lingual (French and English) and the purpose is to share the lessons learnt from radiological incidents that have occurred in the industrial, medical, research and teaching, and other non-nuclear sectors. The website contains a collection of incident reports, categorised according to the sector and the type of application, and a search facility. The reports can be freely downloaded and printed, for example for use in radiation protection training courses.
OTHEA takes forward the work previously done in the UK (ie IRID, which has now been replaced by OTHEA) and in France. As before, to encourage dissemination the incident reports have been made anonymous, ie any information that could identify a particular individual, organisation or site has been removed. Each report contains a brief summary of the incident, the radiological consequences, and the lessons learned. The aim is not to capture every single incident, but to provide a range of reports selected according to the value of the lessons learnt.
For OTHEA to be a long-term success, it needs to be sustained with new reports. Therefore, as well as being invited to access the existing information, users are encouraged to submit new reports that can be considered for inclusion in OTHEA. Details on how to do this can also be found on the website.
HSE's Radiation Team has an ongoing programme of inspection of NHS Hospital Trusts and other hospitals. The principal aim of these inspections is to improve radiation protection at the hospitals and to check compliance with the Ionising Radiations Regulations 1999 and the Control of Artificial Optical Radiation at Work Regulations 2010.
The main areas of concern identified during recent visits are listed below:
HSE has previously published guidance aimed at senior managers within the medical sector, to provide an overview of their responsibilities under ionising radiation protection regulations: HSG223, "The regulatory requirements for medical exposure to ionising radiation: An employer's overview" which is available for free download from the HSE website.
HSE's Radiation Team have significant concerns about the level of compliance with Reg. 15 of the IRR99 in the medical sector particularly with regards to dosimetry and the management of radiation exposures. Indeed, enforcement action against one NHS Trust has been taken recently.
Reg. 15 states that:
Where work with ionising radiation undertaken by one employer is likely to give rise to the exposure to ionising radiation of the employee of another employer, the employers concerned shall co-operate by the exchange of information or otherwise to the extent necessary to ensure that each such employer is enabled to comply with the requirements of these Regulations in so far as his ability to comply depends upon such co-operation
Where an NHS Trust has employees that work with ionising radiations for other employers, in private practice or as a self-employed person then clearly Reg 15 applies. In many cases Trusts are allowing these employees to wear the personal dosemeter(s) issued by the Trust whilst working elsewhere and no exchange of information between the radiation employers, including those that are 'self employed, is taking place. Thus no party can know the origin of any recorded radiation exposures.
Good standards of radiological protection and compliance with the IRR99 cannot be achieved unless the magnitude and origin of all personal exposures can be determined. Neither can they be achieved without proper co-operation between employers. Simply put employees should not work with ionising radiations for other employers or as self-employed person unless the magnitude and origin of their radiation exposures can be determined.
There are a number of solutions to this problem. For instance, the use of electronic dosemeters would assist employers in knowing the magnitude and origin of radiation exposures. Better co-operation between employers is certainly required. In any event employers should ask themselves whether they comply with the details of the Schedule of the recent Improvement Notice-
Where your employees are engaged at work with ionising radiations whilst employed elsewhere or whilst working as a self-employed person ensure that sufficient information on their radiation exposure is exchanged so that:
The International Nuclear and Radiological Event Scale (INES) is 20 years old this year, and UK is an INES member state. INES is a system for promptly and consistently communicating to the media and public, information on the safety significance of accidents or incidents affecting sources of radiation. INES applies to any event associated with the transport, storage and use of radioactive material and radiation sources, whether or not the event occurs at a designated nuclear installation.
INES was developed by the International Atomic Energy Agency (IAEA) and OECD-Nuclear Energy Agency (NEA), originally for nuclear power plants. In operation, it is coordinated and maintained by the IAEA through a computer based repository for events reported to it, called the Nuclear Event Web-based System (NEWS).
In early 2009 a revised INES User's Manual was published (2008 Edition) incorporating extended guidance on the use of the scale and additional information on the wider scope of the scale. Significant events that may be of interest to the media or public should have the rating communicated promptly in an appropriate format for media use. Details of events that are rated at level 2 or above should be submitted without delay to the IAEA database to facilitate international notification. The table below provides some examples of INES rated events involving radiation sources that were notified to IAEA.
|People and Environment||Defence-in-Depth|
|Accident with Wider Consequences
|Goiânia, Brazil, 1987 – Four people died and six received doses of a few Gy from an abandoned and ruptured highly radioactive Cs-137 source.|
|Accident with Local Consequences
|Fleurus, Belgium, 2006 – Severe health effects for a worker at a commercial irradiation facility as a result of high doses of radiation.|
|Yanango, Peru, 1999 – Incident with a radiography source resulting in severe radiation burns.||Ikitelli, Turkey, 1999 – Loss of a highly radioactive Co-60 source.|
|USA, 2005 – Overexposure of a radiographer exceeding the annual limit for radiation workers.||France, 1995 – Failure of access control systems at accelerator facility.|
|Theft of a moisture-density gauge.|
Since the inception of INES the UK has been committed to using the scale and the arrangements are coordinated by a UK government appointed INES National Officer (UKINO). The current UKINO is a member of HSE's Nuclear Installations Inspectorate, who acts independently in his INES role.
In addition, HSE is notified under regulatory requirements of events relating to the more general use of radiation sources eg industrial, medical, educational etc. These events are reviewed by HSE's Radiation Specialists to judge whether they require an INES rating and if it meets the reporting threshold of INES Level 2 or above. Transport related events are reviewed in a similar way by the Department for Transport and notified to the UKINO for onward notification as necessary.
The Association of Heads of European Radiological Competent Authorities (HERCA), which was formed in 2007, has recently approved the content of a 'harmonized European Radiation.
Passbook' which it plans to refer to the European Commission for consideration in the Basic Safety Standards Directive (BSS) revision process which is currently underway. HERCA's press release on this work may be found on the website HERCA/European Radiation Passbook along with the agreed format of the passbook.
Radiation Protection Advisors will note that the format of the passbook is, by and large, identical to that published by HSE for use in the UK in accordance with Regulation 21(3) and 21(5) of the Ionising Radiations Regulations 1999; in which regard, HSE's input to HERCA's work had in part this purpose.
Although HERCA has now completed this work, HSE would, nonetheless, welcome comments on it so that its future engagement with the European Commission on the BSS revision is properly informed by opinion from stakeholders.
Steve Walker, HM Inspector (Nuclear Installations)
There are a large number of companies involved in the road transport of radioactive materials. Some of these only transport small quantities in what are commonly known as 'exempt' or 'excepted' packages in reference to the road transport regulations enforced by the Department for Transport. Unfortunately, there is a common misconception that because the packages are 'exempt' or 'excepted' the IRR99 do not apply. This is not the case and companies involved in the transport of any radioactive materials will need to comply with the IRR99. Furthermore, particular attention will need to be made to the requirements dealing with prior risk assessment, the training of staff and contingency plans for reasonably foreseeable radiation accidents.
One company that didn't fall into this trap is Biocair of Cambridge. They are a specialist logistics company who regularly transport packages containing small quantities of radioactive materials. Having realised that the IRR99 applied to their work they made admirable efforts and achieved full compliance. A rare event in this particularly sector for which they received deserved praise during a recent inspection by a member of the HSE Radiation Team.