- Handling of cryogenic liquids:
- Face masks and gloves are provided in each cell. Protective aprons are
available. Gloves must be used when inserting and removing the transfer
siphon from the dewar. Doing so prevents freezing your skin. It also reduces
the probability of damaging the siphon so that it will be available for your
next transfer.
- More people are injured with liquid nitrogen than liquid helium because it
is more commonly handled directly. Wear gloves when you might touch cold metal
tubing
- Bare feet and open toed shoes, such as sandals are not allowed in the cell
area. Your footwear must provide secure footing on stairs and ladders and some
protection of your feet from spilled liquids.
- Equipment must be arranged in the cell neatly with reasonable working
space. Cables should be out of the way so people don't trip on them or catch
them with moving equipment. Gas bottles must be in the wall mounts. If the
wall mounts are not convenient, ask the Control Room or Operations personnel to
help you do what you want.
- The experimenters are responsible for the cleanliness of the cell during
an experiment and for returning all equipment and supplies to their proper
places after finishing.
- The magnets are powered by one or more ungrounded 500 V / 20,000 A power
supplies that have contacts in each cell. Be aware of where that power is and
make sure that neither you nor your probe comes in contact with this power.
This could lead to severe damage to the experimental equipment or sample not to
mention the experimenter. The power supplies probably will not be damaged.
- The magnet housing is connected to the magnet through the cooling water.
The housing is grounded, however, to be completely safe, treat the magnet
casing as if it could suddenly rise to a 500 V potential at any time.
- High pressure water is in the magnet housing and in the connected pipes.
For this and reasons above do not spend long periods of time on top of the
magnet unless necessary. Please inform the control room if you absolutely must
be up on the magnet platform when there is current in the magnet.
- Do not enter the area around the magnet under the platform. There are
many ways to injure yourself there and no good reason to go in. If you drop
something down there, contact the Control Room to get someone to retrieve it.
- Be aware that strong magnetic fields exist around the magnet. Lines at
the 10G and 100G level are drawn on the floor of the cell. Credit and ATM
cards should be kept behind the 100G line. Steel, iron or other magnetic
objects should be fastened down or kept behind the 10G line. Be especially
aware of compressed gas cylinders. Be very sure that screwdrivers, wrenches
and other hand tools are not left around the magnet. Steel chairs are
NOT allowed in the cells under any circumstances.
- There shall be one person in the cell whenever there is current flowing in
the magnet. Control room personnel are instructed to immediately ramp the
magnet down if a cell is left unattended. It is best to have two persons
present and participating in the experiments. Two people make fewer mistakes,
solve problems quicker, do experimental procedures quicker, and generally make
more efficient use of magnet time. This becomes especially important after
normal business hours when Operations staff are less available. If you need an
extra person temporarily to help with an operation or if you need to leave the
cell and cannot ramp the magnet down.
- Continuous contact between the experimenters and the Control Room must be
maintained over the intercommunication system during operation of the magnet.
The experimenter can start the communication by pressing and releasing the Call
Button on the speaker cabinet and saying, for example, "Cell five calling the
Control Room." Do not press the Call Button after the Control Room has
answered, just speak in a fairly loud voice directly into the speaker cabinet.
- A plastic barrier chain should be across the cell entrance when running.
The experimenter is responsible for the safety of everyone other than
Operations staff, who is in the cell during a magnet run. The experimenter
should warn anyone entering the cell that the field is on and can direct anyone
who is not a member of the Operations staff to leave the cell.
- There is a red Emergency Off button located near the exit in each
cell. It will shut off electric power to all the magnets in use if it is
pressed. In case of an emergency hit this button as you rapidly but calmly
exit the cell. Safety circuits detect magnet and other cell faults and shut
off power in milliseconds, so most cell emergencies are over in less time than
most humans require to react. Panic may cause to you injure yourself.
The
following procedures are under development:
Equipment:
Instrumentation:
Helium & Nitrogen:
Computer:
Etiquette & Other Users:
Cleanup:
Procedures:
Startup & Checkout:
Magnet Control & Communication:
Shutdown:
Return to NHMFL Home Page
Return to NHMFL Operations Home Page
Curator: Scott Hannahs <sth@magnet.fsu.edu>
Last Updated:
