1. Thomas Jefferson National Accelerator Facility Page 1 UITF Progress meeting UITF ODH Discussion How to avoid ODH2 conditions? August 5, 2015

2. Thomas Jefferson National Accelerator Facility Page 2 UITF Progress meeting To refresh your memory… Today Labyrinth with “chicken wire” gate

3. Thomas Jefferson National Accelerator Facility Page 3 UITF Progress meeting

4. Thomas Jefferson National Accelerator Facility Page 4 UITF Progress meeting Cryo lines from CTF along wall GN2 lines along the wall SF6 tank

5. Thomas Jefferson National Accelerator Facility Page 5 UITF Progress meeting Helium dewars: 1,000 liters, 500 liters, 50 liters = 1,550 L ¼ CM LHe capacity, ~ 400 L (?) Total LHe supply from CTF…. Nitrogen line at 80 psi thru a 3/8 inch pipe = 22 cfm or 1,320 cubic feet per hour SF 6 inside vessel that hold HV power supply: 25 ft 3 filled to 70 psi, ~ 54 lbs: total volume if released? 144 ft 3 Helium, Nitrogen and SF 6

6. Thomas Jefferson National Accelerator Facility Page 6 UITF Progress meeting Rough Dimensions Cave 1: 12’ x 12’ x 60’ ~ 8,640 ft 3 Cave 2: 22’ x 54’ x 12’ ~ 14,256 ft 3 Dick Owen made a more exact calculation: 25,704 ft 3 Matt’s loose estimate, total volume: 22,896 ft 3 Exhaust vent to outside Exhaust vent to high bay exit/entrance

7. Thomas Jefferson National Accelerator Facility Page 7 UITF Progress meeting Approved Labyrinth Fresh air pulled through “chicken wire” gate

8. Thomas Jefferson National Accelerator Facility Page 8 UITF Progress meeting Improving the ventilation in Cave2 Add a wall to help direct air flow Add ductwork leading to rear of Cave2

9. Thomas Jefferson National Accelerator Facility Page 9 UITF Progress meeting Dick Owen performed a preliminary assessment…he considered LHe dewars, GN2 and SF6.

10. Thomas Jefferson National Accelerator Facility Page 10 UITF Progress meeting ¼ CM cold by January 2016 HDIce moved into place starting May 2016 SSG building an ODH system, I assume they have planned for enough heads and in the right locations How to avoid ODH2? What accidents are we required to plan for? Can the old ODH assessment be updated to account for additional volume and extra 1550 L of additional LHe? Save a bit of time and labor? Ventilation concerns: ODH related, replenishment of air non-ODH related, comfort? Is it clear what problems we are trying to fix?

11. Thomas Jefferson National Accelerator Facility Page 11 UITF Progress meeting Concrete demolition complete Stairs are next (complete in FY15) Bi-weekly meetings scheduled

12. Thomas Jefferson National Accelerator Facility Page 12 UITF Progress meeting Cryo lines compatible with old and new ¼ CM… Looks similar to our “upgrade injector” front end