Regulation 31

all marks, labels and signs are permanently affixed thereon and clearly visible; and

all user controls, meters, lights or other indicators are clearly visible, readily discernible and clearly labelled to indicate their functions.

on the control panel, separate indicator lights or other equivalent indicators —

to show when the line voltage is “ON” or “OFF”; and

to show when the radiofrequency is applied; and

a clear and reliable indicator of the strength of the field and the frequency of the radiofrequency used.

the static magnetic field strength (Bo) shall not exceed 2.0 T;

the rate of change of magnetic field strength with time (dB/dt) shall comply with any of the provisions of this sub-paragraph —

each magnetic resonance imaging apparatus shall have a maximum dB/dt of not more than 6 T/s;

the licensee is allowed to utilise values of dB/dt that may exceed the 6 T/s value under the following conditions:

for axial gradients:(1)dB/dt < 20 T/s forτ ≥ 120 µs;(2)dB/dt < 2,4000/τ T/s for12 µs < τ < 120 µs(3)dB/dt < 200 T/s forτ ≤ 12 µs,where the pulse width (τ) is the width in microseconds of a rectangular pulse or the half period of a sinusoidal dB/dt pulse;

dB/dt for transverse gradients is less than 3 times the limits for axial gradients;

with respect to radiofrequency heating (SAR), the licensee shall take appropriate measures to ensure the following are complied with:

SAR ≤ 0.4 W/kg for the whole body;

SAR ≤8.0 W/kg for spatial peak in any one gram of tissue;

SAR ≤ 3.2 W/kg averaged over the head; and

exposure to radiofrequency magnetic fields shall not be sufficient to produce a core temperature increase in excess of 1°C and localised heating to greater than 38°C in the head, 39°C in the trunk and 40°C in the extremities;

the licensee shall establish a warning zone where the magnetic field exceeds 5 gauss to ensure the safety of persons with cardiac pacemakers or other implanted devices; and

the licensee shall provide a venting system to remove gases resulting from a quench directly to the outside of the building for a superconducting magnet system.