B911 access system requirements

Thursday 3 Jul 2025, 13:30 → 14:30 Europe/Zurich

B911 door

• EN-AA can easily install a dosimeter/card reader at the new door of b911. A switch from dosimeter to card can be easily performed via a software change. The costs related to the system are little
• The PAD/MAD is to be removed beginning of LS3 for easing access to ECN3 for dismantling/CE/installation works. Another access control with dosimeter reader is then needed with 2 options:
  • Advantages:
  • Same as for BDF/SHiP
  • Existing delimitation via b911 door
  • Easy installation of dosimeter reader at b911 and no need for installation of new access doors
  • Allows temporary buffer zone for radioactive equipment from TCC8/ECN3 (otherwise no buffer as outside only for non-radioactive equipment)
  • Easy switch from dosimeter to card via software change in case at some point underground area can be declassified (half a day)
  • Potential disadvantages:
    • Heinz Vincke told me that truck drivers for LS3 will even have Controlled Radiation Area training (not only Supervised) as discussed with Caterina Bertone
    • This constraint is the case for other Supervised Radiation Areas (e.g. EHN2 and AD)
    • Doors should be only kept open while operation takes place (e.g. truck inside)
    • Clear Radiation Area signage must be in place and entering the area without a dosimeter is a professional fault
    • This risk is also the case for other Supervised Radiation Areas (e.g. EHN2 and AD)
  • Truck drivers would need a dosimeter
  • If the truck door is open, someone could enter the area
  • Advantages:
  • Easy access to b911 without any access control / dosimeter
  • Disadvantages:
  • No buffer area for radioactive equipment in b911 possible
  • B911 is used to transfer hot equipment from TCC8. During this time access must be controlled and it must be ensured that people entering the building have a dosimeter. This is not the case without a dosimeter reader at the b911 door
  • And additional door would be needed at PAD/MAD with a dosimeter reader
  • Installation of additional card reader at b911 door would also be needed
1. Classification of b911 as Supervised Radiation Area
2. Classification of b911 as Non-designated Area
• Claudia believes it is clear that Option 1 should be pursued. However, she welcomes any comments (I suggest until 23/07), and a follow-up discussion can be arranged if necessary.

 

 

Access container

• The access container in TCC8 must be installed before the blue ventilation wall (sector door) will be removed
• The container placement should in principle be downstream of QNL.X1010046. The current fence is located upstream of it. @Jean-Louis Grenard, to check, together with RP, if the fence can be kept at its current location or should be moved downstream
• In case the downstream part will be declassified to a Non-designated Area at some point, the access container would have to be kept in place as the floor still requires a Simple Controlled Radiation Area Classification. @Jean-Louis Grenard, could you please prolong the request for the access container?

 

General

• The underground areas will be a worksite category 1 for which access must be controlled in a clear way
• Access via TDC85, galleries and b918 must generally be closed (only emergency path), unless for certain times a derogation is required (e.g. for decabling) (see attached slide)
• B918 doors are end of sector doors that do not allow for an easy implementation of an access control. However, b918 has access control

13:30 → 14:00 HI-ECN3 safety systems

Speakers: Boris Morand (CERN), Claudia Ahdida, Michael Dole (CERN)

B911_access_system.pdf

B911_access_system.pptx