Working alone or out of hours in the M.R. Centre
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Instructions:-

You may not undertake any of the activites listed in Groups A, B and 
C unless you have been properly trained, are aware of the relevant 
hazard assessments, and are aware of the emergency procedures. In the 
following a 'buddy' is an appropriately skilled MR worker or student who has been properly trained 
and is aware of the emergency procedures etc and who has been previously 
agreed with an MR Competent Person or MR advisor.

1.   When working out of hours with a buddy present in the building, the 
book in reception must be signed, then the activities listed in groups 
A, B and C may be undertaken.     

2.   When working alone during normal working hours you may carry out 
the activities listed in groups A and B , You may not undertake activities
listed in group C.

3.   When working alone, out of hours (before 8.00 am or after 7.00 pm, 
or weekends and holidays) you must sign the book in reception, then you 
may carry out the activities in group A.  You may not undertake the 
activities listed in groups B and C.

GROUP
-----

A    Running scanner machine, altering and testing scanner software, 
     changing phantoms and RF coils.
     Changing low voltage BNC connectors.
     Resetting trips on Techron and RF amplifiers. 

B    Scanning volunteers using established protocols.
     Filling cryostat.

C    Work involving the removal of safety covers including:-
     Altering gradient coil connections.
     RF amplifier wiring.
     Techron amplifier wiring.


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Basis:-

The HSE does not prohibit solitary working, except in certain 
circumstances, provided that suitable training is provided and that 
emergency procedures are in place.
HSE IND(G)73(L) 20M 9/90

The University Health and Safety Code of Practice on electrical 
safety (1995 part C p6) states that work involving extensive 
exposure to live conductors at dangerous voltages should only be 
carried out by a competent person within sight and sound of another
competent person.

The University safety handbook under 'General Precautions'(1991 p15) 
stresses the potential dangers of carrying out experimental work 
at night and states that the practice should be strongly discouraged. 
It goes on to say that such work must only be carried out with the 
knowledge of the Dept. Safety Officer and the consent of the Head of 
Dept. and that if such work is essential, every effort should be 
made to ensure that another worker is within hearing distance and 
that security staff should be asked to make regular contact. Under 
'General Laboratory Instructions' (p20) it is stated that out of 
hours working must be subject to appropriate Dept. regulations.

The Physics Dept. Safety Handbook (1994/5 4.14) states that ouside 
normal working hours users must sign the book in reception, and that 
laboratory work should not be carried out by a person who is alone 
in the building.

The instructions are intended to interpret this in the particular case 
of the operation of MR imaging and spectroscopy machines in the MR 
Centre, when required to operate outside of normal hours, with safety 
as the overriding concern. The assumption here is that the principal 
risk to solitary users of research MR scanners is from electric shock, 
flash burns, RF burns or electrically induced fire. These instructions 
are aimed at restricting the exposure of solitary users to voltages 
less than those deemed dangerous. (50V ac or 120V dc in dry conditions), 
and preventing the solitary user from accessng any wiring capable of
producing such effects. Other hazards in particular applications may 
negate this assumption requiring different instructions.