Bruker BioSpin NMR Fourier 300, Руководство по планировке объекта

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B127527_00_03
Safety
contact with these liquids can cause frostbite. The system manager should regularly
check and make sure that evaporating gases are free to escape from the magnet
, i.e.
the release valves must not be blocked. Do not attempt to refill the magnet with helium
or nitrogen unless you have been trained in the correct procedure.
2.3.1 What is a Quench?
A magnet quench is the spontaneous breakdown of superconductivity in a partially or
fully energized magnet. The stored field energy is transformed into heat, leading to a fast
evaporation of liquid helium. During a quench, an extremely large quantity ,
~40 m
3
( 1,400 ft
3
) of helium gas is produced within a short time.
Helium and nitrogen are non-toxic gases. However, because of a possible magnet
quench, where upon the room may suddenly fill with evaporated gases causing
potential danger of suffocation. Adequate ventilation must always be provided and it is
recommended that any person should leave the room.
2.4 Emergency Planning
Due to the strong magnetic fields and presence of cryogens when using NMR systems,
it is important to define and communicate what to do in case of problems or an
emergency. An
Emergency Plan can be defined as a documented set of instructions on
what to do if something goes wrong. Emergency Plans are often defined as part of the
Standard Operating Procedures (SOP), or as a stand-alone document. In any case
every NMR laboratory should have an Emergency Plan in effect in case of problems or
emergencies.
As every organization has its own policies and procedures, as well as varying laboratory
layouts, an Emergency Plan should be individually defined for each laboratory as
appropriate. Upon request Bruker can provide useful information on emergency
planning.
2.5 Fire Department Notification
It is recommended that the magnet operator introduce the fire department and/or
local authorities to the magnet site. It is important that these organizations be
informed of the potential risks of the magnet system, i.e. that much of the
magnetic rescue equipment (oxygen-cylinders, fire extinguishers, axes etc.) can
be hazardous close to the magnet system. On the other side, their expertise and
experience can be invaluable in creating an Emergency plan.
• Within a NMR laboratory CO
2
magnetic fire extinguishers must NOT be used.
Breathing equipment which uses oxygen tanks made out of magnetic material can
be life threatening when used close to a magnet system which still has a magnetic
field present.
• Helium gas escaping from the system must not be mistaken for smoke. Instruct the
fire department and technical service not to extinguish the magnet system with
water. The outlet valves could freeze over and generate excess pressure within the
system.