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Lena Johansson Senior Radiation Protection Expert

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1 Lena Johansson Senior Radiation Protection Expert
ESS Handbook on Radiation Protection Chapter 2 – General Safety Objectives Lena Johansson Senior Radiation Protection Expert 10 April, 2018

2 Intro This is a chapter that is the most draft (still shared with ESHAC) that relies on early development of ESS definition of rad zones. Depending partly on updates of the ESS Definition of Supervised and Controlled Radiation Areas. Etc. And the links with Chapter 4 (working with IR) and 6 (dosimetry).

3 Chapter 2 – General Safety Objectives
TOC General Safety Objectives 2.1. Dose Limits and Dose Restrictions 2.2. Pregnant women 2.3. Breastfeeding women 2.4. Limitation of radiation dose as part of work planning 2.5. Permissible dose in emergencies 2.6. Contamination Control Contamination control of personnel Prohibition of consuming food and smoking Open wounds Contamination surveys Medical treatment with radioactivity 2.7. Radiography 2.8. Barriers and signs 2.9. Categorisation of workers and radiological areas Categorisation of workers Medical surveillance Non-designated areas Supervised area Controlled area

4 SSM conditions # Request 7-4
a description of procedures for information on and protection of pregnant or breast-feeding workers. 7-5 a description of ESS's standing as to whether people under the age of 18 shall be allowed to work with radiation sources. 7-13 a description of how current workplaces should be categorised during this trial operation stage. 7-14 a description of how workers shall be categorised during this trial operation stage. 7-15 a description of how ESS shall verify that categorisation, according to the above points, is correct. 7-16 a description of local work procedures for how the work is to be carried out and which protective measures shall be taken during work within the controlled and protected areas. 7-17 further descriptions of how controlled and protected areas shall be marked.

5 SSM conditions # Request 7-45
a clarification as to whether only Category A assigned workers or all employees will be subject to requirements on medical examinations. 7-46 a description of procedures that ensure medical examinations are carried out at least every three years, as long as the person in question remains at work. 7-47 a description of procedures that ensure a periodic check of the state of health occurs in the interim years when no medical examinations are carried out. 7-48 a description of procedures that ensure medical certificates from external category A assigned workers are checked and documented. 7-49 a description of procedures that ensure the results of the medical examination are utilised in the work. 7-50 a description of procedures that ensure a medical examination is carried out immediately after it has been found that any person has exceeded any of the annual dose limits prescribed by the Swedish Radiation Safety Authority.

6 Rad zoning document - ESS-0001786

7 Work area classification
MANAGEMENT OF WORK WITH IONISING RADIATION non-designated designated radiation areas Annual dose limit ‘public’ area (non-permanent) Supervised area Controlled area Restricted controlled area Highly restricted contr. area Effective dose < mSv (< 1 mSv) < 6 mSv < 20 mSv ambient dose rate < μSv/h (< 0.5 μSv/h) < 3 μSv/h < 25 μSv/h < 2 mSv/h more than 2.5 mSv/h Eq. dose to lens of eye < 15 mSv –”– Eq. dose hands/feet OR skin < 150 mSv < 500 mSv Change EPD!! (DMC3000, Ida fixes) Check dose limits restricted occupancy ESS

8 Updates to rad zoning document – discussed proposals
Rename the White zone to “non-designated area” instead of “Public area” Refer to White zone as “non-designated area” and the radiation zones (supervised and controlled) to “designated area”. Not call the Blue zone “unrestricted” Controlled area. Should be called only “Controlled area” or to add another sub-label. One appreciated suggestion was “Simple Controlled area” (like CERN) which would go well with the Yellow “Restricted Controlled area” and the Red “Highly restricted Controlled area”. Another suggestion was “low level” Controlled area. Keep maximum dose rate of Blue zone at 25 Sv/h. because it is not a permanent workplace (25 Sv/h *2000hr = 50 mSv > 20 mSv limit) and because entering a controlled area will not be allowed for personnel with a personal dose already at 10 mSv, as well as the GSO constraint of 2 mSv per person, it is not considered a risk that personnel will get more than 20 mSv in 12 consecutive months. It was also noted that lowering dose rate limits would cause a huge cost due to shielding already designed for the upper limit. It was agreed to replace “External Whole Body Dose Rate” with “Ambient equivalent dose rate”, as this is the correct term. Ambient equivalent dose rate H*(10) is what is measured with dose rate monitors. It is the operational radiation protection quantity to estimate the Effective dose (i.e. whole body dose).

9 Updates to rad zoning document – further discussions and consequenses
From (ESS internal) meeting minutes: It was decided that we won’t require every owner of an ESS document which states the radiation limits or dose limits to be updated immediately (except the 3 core documents listed above). GM suggested that we will inform our ESS colleagues of the changes now and enforce the changes from the next revision of their documents. It was agreed that the dose limits in ESS should keep reflecting the legal limits, and not the GSO limits. This means no change to the document. It was agreed that the personal maximum dose limits for access to a Controlled area would be decreased to 10 mSv such that personal dose in case of an H2 event (10 mSv) does not exceed national limits of 20 mSv. This was in fact changed already with last GSO revision, but never updated in ESS A new high radiation area called “Prohibited area” was discussed. It was recommended by the ESHAC committee at the 7th meeting (9–10 Oct 2017). FJ informs that this was proposed in the past already. GM explained that the Red zone “Highly restricted controlled area” is in principle already prohibited. Nothing was decided.

10 Updates to rad zoning document – further discussions
From (ESS internal) meeting minutes: It was agreed to only allow Category B rad-workers in Supervised Area (for now), and limit work in Controlled Areas for Category A rad-workers. This means ESS needs to be updated.  IB, LJ is for a decision to only allow Category A in Controlled areas, and interpret the SSM regulations in this way. Already existing constraints for Controlled area speak for denying access by Category B rad-workers (H2 events, maximum personal dose, dose rates, contamination). FJ and GM argues that Category B should be allowed to work in Blue controlled zone, and that this has been discussed and approved by SSM in the past. GM (or TH) to find written documentation on this discussion. Discussion continued about additional costs of “upgrading” Category B workers to Category A to allow them to work in Blue Controlled zone. Medical examination, extra RP training and dosimeters that has to be evaluated twice as often was included. It was agreed that personal dose constraints for allowed access to Supervised area cannot be the same for Category A and Category B workers. It was not decided how or in which database to solve it, discussion including the LMS, Access system and Data Protection Act. The problem is a Controlled area is always adjacent to supervised area – never a white zone. Thus, if an individual is banned from Supervised area due to annual dose exceeding 3.5 mSv, a Category A worker cannot get through to a Controlled area if his/her accumulated dose is between 3.5 – 10 mSv.. The question of how to calculate the “committed dose” for internal exposure and how to incorporate it in the dose evaluation was raised. Not solved yet.

11 Updates to rad zoning document – discussed proposals
Mandatory update New legal dose limits As per recommendation from the European directive 2013/59/EURATOM the annual effective dose limit has been decreased from 50 mSv to 20 mSv (keeping 100 mSv in five years) and the annual equivalent dose limit to the lens of the eye is decreased from 150 mSv to 20 mSv. These changes will be effective from February 2018, including among other the following new legislation:

12 Other remaining questions
Medical certificates that have “conditions”, how are they handled and flagged ? Medicals linked to Access system and LMS. Who sets the categorisation of staff and where is it documented? Only Cat A to do medical? (probably not) Possibly change title in order not to be confused with ESS General Safety Objectives?

13 Thank you!


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