2018-10-01 Thomas Hansson & Francois Javier, ESH ESHAC #9 Update on ESS General Safety Objectives and Categorization of Workers and Public 2018-10-01 Thomas Hansson & Francois Javier, ESH

ESS General Safety Objectives (GSO) Existing version; ESS-0000004 rev 5

ESS General Safety Objectives (GSO) Existing version; ESS-0000004 rev 5, Table 2 Rad workers with safety task Rad workers without safety task GSO rev 6 “Safety task” means credited actions performed by a worker in order to reach the facility “Safe state” and comply with objectives for public. Not for workers.

ESS General Safety Objectives (GSO) Draft version; ESS-0000004 rev 6 ESS objectives (effective dose, mSv) Operating conditions and likelihood (per year) of initiating event Exposed workers with safety task without safety task Non exposed workers Public (off-site) Normal operation - H1 (including events with F≥1) Dose limit 20 mSv/year   Dose constraints per year 2 mSv on average 10 mSv individually 1 mSv/year Dose constraint 0.3-0.5 mSv/year 0.1 mSv/year Anticipated events - H2 F ≥ 10-2 Design criteria 20 mSv/event Plan protective action based on realistic estimations for typical cases and applying Alara via a respective ESS committee and an established ESS guideline. 0.1 mSv/event Unanticipated events - H3 10-4 ≤ F < 10-2 1 mSv/event Improbable events (DBA) – H4A 10-6 ≤ F < 10-4 Improbable events (DBA) – H4B 10-4 ≤ F H2 and H3 combined with CCF N/A Highly improbable events – H5 10-7 ≤ F < 10-6 50 mSv/event Excluded from further evaluation since it is an acceptable residual risk. 100 mSv/event Extremely improbable events F < 10-7 Draft In black defined by SSM, and in blue established by ESS.

Plan protective action (H2-H3-H4A) - Exposed workers, without safety task example Redesign System of interest System design Still to be classified as Worker Safety Function (WSF) and designed according to conventional standards Option: Mitigate event Based on quantitative assessment. No need for workers to act/react. Event Scope: ionizing radiation. Qualitative assessment of consequence: Increase of radiation levels Increase of contamination levels inside area Redesign Detection & Alert Options Detection inside area Physical parameter to detect? rad/contam. levels or a linked process parameter. Quantitative assessment needed to set trigger point. Alert inside area Alert outside area Alarm: Sound, Light Awareness Awareness Active dosimeter * Added value with detection/alert? Difference in reaction time? 𝛥t No React Procedures/training always needed. Also check possibility to evacuate. Action Evacuate In all workplaces Quantitative assessment ok? Acceptable impact (mSv) ? Criteria needed if to do quantitative assessment Option 1: established criteria in GSO Option 2: judgement/criteria case by case Yes Quantitative assessment (Dose to worker) In relevant workplaces based on quantitative assessment In relevant workplaces based on qualitative assessment Yes No

Workers - GSO guideline proposal Operating conditions Likelihood of initiating event Exposed workers without safety task Non exposed workers (including public on site) Normal operation - H1 (for workers including events with F≥1) Dose limit 20 mSv/year Dose constraints: 2 mSv (average) 10 mSv (most exposed) Dose limit 1 mSv/year Dose constraints: 0.3-0.5 mSv Anticipated events - H2 F ≥ 10-2 10 mSv to 20 mSv/event 0,5 to 1 mSv/event Unanticipated events - H3 10-4 ≤ F < 10-2 20 to 50 mSv/event 1 to 10 mSv/event Improbable events (DBA) – H4A 10-6 ≤ F < 10-4 50 to 100 mSv/event 10 to 50 mSv/event Nota : 1/ Deterministic effects: relationship between effects severity and dose received - threshold existence: from 100 mSv (ICRP 103) 2/ Stochastic effects: no relationship between dose and effects severity but relationship between dose and likelihood of occurence of effects – no evidence of threshold existence so use of the precautionary principle (even if no exces of cancer found below 100 mSv) – ICRP 103 : assuming linear response at low doses, the combined detriment due to exces cancer and heritable effects is around 5% per Sv (cancer : 5.5.10-2 Sv-1 for public and 4.1.10-2 Sv-1 for adult workers/heritable effects: 0.2.10-2 Sv-1 and 0.1.10-2 Sv-1) 3/ Euratom 2013/56: Emergency occupational exposure 100 mSv (500 mSv in exceptional situations)

Categorization of people - ESS employees - Contractors - Consultants - In-kind - Users/scientists* - Trainees - Students - etc. Workers Exposed workers > 1 mSv Cat A > 6 mSv Cat B < 6 mSv For instance apprentices & students 16-18 years, but only with access to supervised areas. Case-by-case pregnant and breastfeeding women could be Cat B but then only with access to supervised area and still to be below exposure of 1 mSv, and no access to controlled areas. Non exposed workers < 1 mSv Workers without access to supervised* or controlled areas. Specifically pregnant and breastfeeding women Draft Exposed workers with or without safety task * On-going discussion within ESS if users/scientists can deviate from this rule as long as they stay below 1 mSv and comply with Cat B requirements (training/ dosimeter) but NOT to be officially categorized as Cat B. ESS will only request that the home institute categorize the user/scientist. Note 1: Even if Cat A and B have access to supervised and controlled areas from a radiation point of view, certain areas within supervised and controlled areas might require specifically authorized access for other reasons than radiation and might therefore be fenced-off or equipped with limited access via surrounding doors.   Note 2: Non exposed workers are not allowed to work in supervised areas. Neither in controlled areas. Note 3: Visitors and guests are excluded from the structure above, but will be considered as non exposed workers.

Thank you! Questions?