Difference: VeloAccessIP8 (3 vs. 4)

Revision 42007-11-28 - PaulaCollins

Line: 1 to 1
META TOPICPARENT name="VELOCommissioning"
Below some hopefully helpful info for new collaborators that also need access to work in the pit (=IP8) of LHCb.
Line: 67 to 67
  Don't bother about dosimetry (yet).

Please note that working around the beam pipe requires special precautions

  • In general the beam pipe is very fragile, and surrounded with fragile sensing equipment. Do not approach it, not touch it, and certainly not drop anything on it! Remember that upstream of the VELO the beam pipe is relatively strong and well attached, but downstream from the VELO exit window it relies only on the protection which has been installed, and which may be incomplete in places.

  • During evacuation there are additional risks. If the beam pipe is punctured and suffers implosion, this could seriously damage your hearing, and expose you to a possible risk of coming into contact with beryllium or breathing beryllium dust.

  • For these reasons, when the beam pipe is under vacuum, people are forbidden from working above it, or approaching within 3m, for the region downstream of the VELO. This situation will be clearly signalled with signs around the area. Around the VELO close cabling work is also forbidden. Work is permitted under the false floor, but should be discussed on a case by case basis. The personnel involved will receive relevant advice on how to behave around the area.

  • During bake out there are again additional risks. The isolation may be imperfect, and even on the outside of the isolation may reach above 100 deg C. There is also a risk to the equipment, the disconnection of one thermocouple may result in the entire 2 week beam pipe commissioning period having to be repeated. And of course the area is heavily used by the beampipe team. During this time NO work is allowed around the VELO.

  • Note that, under normal circumstances, the evacuation of the beam pipe is an infrequent occurence, but will occur at least one more time before the startup.

  • In conclusion: the work around the VELO has for safety reasons to be closely coordinated. If you plan to work around the VELO please make sure that you contact Paula Collins (Paula.Collins@cernNOSPAMPLEASE.ch, +41764870411) or Eddy Jans (eddy@nikhefNOSPAMPLEASE.nl, +31206922085 or +41764872192) to receive their OK and possibly additional safety instructions.
This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback