Safety - Lessons learnt from the design, commissioning and operation of the HIE-ISOLDE cryomodules Safety overview ESS 8 June 2016 AP.Bernardes/EN on behalf of HIE-ISOLDE project

Outline Introduction Safety authorization process Condition for access Feed-Back on 1rst commissioning phase Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS2

Outline Introduction Safety authorization process Condition for access Feed-Back on 1rst commissioning phase Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS3

Introduction 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS4 Proton beam = Primary Beam (1.4 Gev and 2µA) Isotopes beam = Secondary Beam (20 and 500 epA – Stable beam ) Proton beam from PSB: 1.4 GeV, 2 µA 3e13 protons/pulse Cycle: 1.2 s 3 kW average power HIE SC Linac Upgrade existing post-accelerator 3MeV/u  10 MeV/u for A/q=4.5 with supraconducting LINAC

Introduction 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS5 Tunnel located in the middle of an experimental Hall Tunnel 20m long

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS6 Introduction Management meetings: -International Advisory Panel -Steering Committee -HIE-ISOLDE management meeting Operational meetings: -Integration meeting -HIMAC (HIE-ISOLDE- Machine-Commissioning WG)

Outline Introduction Safety authorization process Condition for access Feed-Back on 1rst commissioning phase Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS7

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS8 Safety autorization process HSE safety clearance RF and Beam permit authorization by BE Authorization to start physic for HIE-ISOLDE Safety checks required to provide Safety clearance well defined prior commissioning start-up Extra Safety checks may be requested by the project Safety checks required to provide Safety authorization well defined prior commissioning start-up

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS9 Safety authorization HSE safety clearance In addition a safety file for the project has to be approved prior the HSE clearance as well as cryogenic risk analysis

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS10 Safety authorization HSE safety clearance “According to the CERN mechanical Safety rule, the HIE- ISOLDE cryomodules are a classified as a special equipment. As such the HSE Unit shall verify the compliance of the equipment with the applicable safety requirement." Since this equipment operates at a pressure (PS) superior to 0.5 barg the safety requirements are defined on the basis of the directive 97/23/EC concerning pressure equipment.

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS11 Safety authorization process HSE safety clearance

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS12 Safety authorization process RF and Beam permit authorization by BE Personal Safety System (PPS) Patrol BE-DSO tests on PPS Radiation Protection (shielding, RP monitoring, Fluka simulation)

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS13 Safety authorization process Signed by: Commissioning project leader Project Safety Officer BE (Beam) Departmental Safety Officer Radiation protection physicist Operator in charge of the HIE-ISOLDE LINAC Section Leader in charge of PS operation RF and Beam permit authorization by BE

Outline Introduction Safety authorization process Condition for access Feed-Back on 1rst commissioning phase Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS14

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS15 Condition for access Suppressed by design

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS16 Condition for access Suppressed with temporary measures

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS17 Condition for access Radiation hazard used to define access system Cryogenic hazard used to define condition of access

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS18 Condition for access Radiation hazard used to define access system 300 μSv/h 10 μSv/h40-50 μSv/h X-Ray production from cavities: Normal operation: few mSv/h RF conditioning: 20 mSv/h He processing: 350 mSv/h  Used to size LINAC shielding 350 mSv/h

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS19 Condition for access Radiation protection hazard used to define access system If one key is removed from HIE- ISOLDE LINAC key box  RF is stopped in all cavities (Cryomodules, IHS, 7 gaps, 9 gaps). No interlock on cryogenic system (only info) Key needed to open the tunnel

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS20 Condition for access Cryogenic hazard used to define condition for HIE-ISOLDE tunnel access (and tunnel roof) Access condition with pressure relief devices vented outside tunnel (He tank and vacuum vessel)

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS21 Condition for access Rupture disk routed outside tunnel (He tank and vacuum vessel)

Outline Introduction Safety authorization process Condition for access Feed-Back on 1rst commissioning phase Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS22

Feed back 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS23 Discussion for access start as soon as the tunnel is closed! Work inside tunnel is needed Discussion for work authorization are simplified by pressure relief devices venting outside the tunnel

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS24 Feed back Scenario possible with access on tunnel or on roof! Burst disk event – August 2015

8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS25 Feed back He release chimney from cryomodule Position of victim (Earing complaint) Oxygen Deficiency and cold burn hazards were managed But noise impact was underestimated  Experimental hall was evacuated spontaneously by all users  1 person complained about earing trouble Acknowledgement: T.Otto

Feed back 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS26 Cool down procedure changed to cool down permit from project (tested this year) Extra safety checks from HIE- ISOLDE

Feed back 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS27 On tunnel roof, temporary fences replaced by definitive ones Tunnel roof door is interlocked with RF Work access inside tunnel still restricted to authorization No solution identified for noise issue!

Outline Introduction Safety authorization process Condition for access Feed-Back on 1rst commissioning phase Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS28

Summary 8 June 2016Safety review of the spoke and Elliptical Cryomodules - ESS29 At CERN Safety clearance to start commissioning is given in tree stages: By HSE unit By BE (Beam) department By project Type of access control was defined by radiation protection assessment Access condition were defined by cryogenic hazard. Pressure relief devices venting outside tunnel helped a lot to authorize work inside tunnel Noise impact in case of Helium release was underestimated