Hi Rensheng,
I would think it would be safest to take down the field in a controlled manner. And then passively and slowly vent out the gases through a suitable tubing ending outside the building. Don’t let the gases evaporate inside the room (helium will expand about 750 times).
Just my two oere.
73, Peter
> On 9 Jul 2015, at 17:23, Luo, Rensheng <luor_at_umsl.edu> wrote:
>
> Hello,
>
> We plan to decommission a magnet. Is it okay to open the ports and let gases to boil off at short time? If doing so, how long does the room O2 level recover to be safe for people to go to the nmr room? Another way we think is to stop refill LHe but keep refill LN2 until magnet goes. Does this way work for safe?
> Thanks
>
> Rensheng
>
> -----------------------------------------------------
> Rensheng Luo
> Chemistry &Biochemistry Department
> University of Missouri-St Louis
> 315 Benton Hall, One University Blvd
> St Louis MO 63121
Peter Lundberg, PhD, Professor
University of Linköping and University Hospital of Linköping Radiation Physics and CMIV
Postal address:
Peter Lundberg
Radiation Physics
University Hospital of Linköping
S-581 85 Linköping, Sweden
Mail peter.lundberg_at_liu.se
Ph +46-(0)10 - 103 2790
On MR-Education
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Received on Sun Jul 12 2015 - 22:10:14 MST