1. EHN1 Cryogenic Integration Requirements David Montanari / Johan Bremer Jun 18, 2015 Rev. 1

2. Outline Cryogenics design status Preliminary safety considerations Draft of cryogenics infrastructures 2Jun 18, 2015EHN1 Cryogenic Integration Requirements

3. Cryogenics Design Status We have now starting working on the cryogenics design of the WA105 6x6x6 and DUNE Single Phase prototype. We have looked at potential failure modes (of the cryostat and cryogenic systems) to provide a preliminary feedback for the emergency ventilation in case of LAr spills. We are preparing a summary of our analysis with the mitigation strategies that we would like to implement to reduce the eventual risk for people. We have prepared a preliminary Process Flow Diagram (PFD) for the cryogenic systems that will serve both detectors. 3Jun 18, 2015EHN1 Cryogenic Integration Requirements

4. EHN1 (From Vincent C.) 4Jun 18, 2015EHN1 Cryogenic Integration Requirements

5. Summary of preliminary safety analysis Safety of personnel is the number priority: evacuate the personnel should a ODH occur. Always guarantee two ways of egress. During normal conditions, there will be no personnel working at the pit level, they will all be working at the top. Access to the pit level will be controlled. Signs should be posted to notify personnel. ODH alarms will be in place. An emergency fan will automatically turn on and vent the vaporizing GAr outside the building. Suction to be located near the bottom of the cryostat at about 1.5 m from the floor (exact location TBD). Based on the worst credible scenario that we have identified, the size of the fan is ~13,000 m 3 /hr. 5Jun 18, 2015EHN1 Cryogenic Integration Requirements

6. LAr System 6Jun 18, 2015EHN1 Cryogenic Integration Requirements

7. LN2 System 7Jun 18, 2015EHN1 Cryogenic Integration Requirements

8. Current Infrastructure needs for cryogenics (DRAFT) Several penetrations through the building to take the cryogens in and release the vents out. Platform around the perimeter of the cryostat at the top (in the back or along one side) for the equipment that needs to be in the vicinity of the detector (GAr condenser, LN2 phase separator, etc.). 8Jun 18, 2015EHN1 Cryogenic Integration Requirements

9. Summary We have performed a preliminary safety analysis and we are writing a summary. We are starting to look at cryogenic system design. 9EHN1 Cryogenic Integration RequirementsJun 18, 2015