industrial radiography equipment need for a review of the effectiveness of the implementation of iso...
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Industrial Radiography EquipmentNeed for a review of the effectiveness of the implementation of ISO 3999?IAEA Technical MeetingVienna, 23-27 June 2014Richard van [email protected]
Radiography Equipment at Applus RTD
Make and type varies between Business Units / CountriesMaintenance is done in-house and by third parties
If maintenance is done in-house then the employees are trained and authorized by the manufacturer
In the past RTD proposed and made several improvements of exposure devices based on the experience of use in the field which let to a reduction in the number of equipment malfunction
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Maintenance program items
Equipment is subject to scheduled calibration / inspection routine (Quarterly)Radiographers inspect all equipment prior to use / daily and records are keptAny abnormal events are required to be forwarded to their RPO / Ops Managers, Typically equipment will be swapped out for maintenance or repairElectrical equipment is inspected and tagged “Fit for Use” as per scheduleMonitoring equipment checked prior to mobilization to jobEquipment history (inspections, repairs, problems, etc) is maintained via records
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Specifications Exposure Devices ISO 3999
5.4 Safety devices 5.4.1 Securing devices
• “It shall not be possible to lock the exposure container unless the source assembly is in the secured position”
5.4.2 Indications of secured position or not• “The apparatus shall be designed such that it is possible to
determine if the source holder is in the sercured position from a distance of at least 5 m.”
5.6 Source-assembly security• “It shall be possible to connect or disconnect the source
assembly from the end of the control cable without the use of any tool, …”
Safety / Securing Devices may fail /1
The bar is behind the key lock.When the guide tube is not connected, the key lock cannot be openedOver time, due to wear and tear, the “golden” part cannot be pushed away far enough by the guide tube.
Safety / Security Devices may fail /2
Selenium GammamatSometimes the lock only closes half way (1)Cause:
Source assembly can be pulled back too far (2 vs. 4)
Slider plate gets stuck behind source assembly (3)
Possible Root Cause: Manufacturing not
according to design specification
• Too much tolerance allowed• Materials used during
manufacturing are of lesser quality than materials used during endurance test
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2 3 4
Underlying (Root) Causes?
Design of Exposure Devices shall ensure continued operation under normal conditions of use. This shall be demonstrated by satisfactory performance of the tests indicated in clause 5.8 of ISO 3999.Are exposure devices always manufactured according to design specifications, e.g. with respect to the quality of used materials and tolerances in the production of its constituting parts?Do the tests sufficiently account for the conditions under which the devices are used in the field?Are end users sufficiently involved in determining the design criteria to make use of their knowledge and experience?
What is their representation in the working group that drafts ISO 3999?
Consequences of failing safety devices
Unsafe operations potentially leading to radiation incidentsSource retrieval becomes more complicated, potentially leading to more severe consequences
What to do about this?
Performance of Exposure Devices and their safety and securing devices under the conditions in which they are used in the field should be reviewed and evaluated
Preferably by an independent party Perhaps via a study on behalf of the IAEA?
Based upon this, the design criteria including relevant test (ISO 3999) and consequently the design for these devices, and their manufacturing could and should be improved
What to do further?
Improving the dissemination of information Obviously on lesson learned from accidents in
which equipment malfunctioning was a cause But also on other incidents and events that had
the potential for becoming or contributing to and accident and in which equipment malfunctioning was a cause
Setting up an international database and promote the industry to use it both by providing information and using it (per ISEMIR initiative)