Skip to main content
This site will look better in a browser that supports web standards, but it is accessible to any browser or Internet device.

QUESTIONS
» MRI Safety

Exposures, limits, safe systems of work. This section explores safety issues in magnetic resonance imaging.

« Question list

Static Magnetic Field Limits

Answer this...

What are the upper and lower limits of the two level approach for patients and volunteers, for the static magnetic field? (UK)

Patient and volunteers:Lower Level (T)Upper Level (T)
Trunk and head2.54
Limbs44

These are the HPA-RPD (was NRPB) static magnetic field restrictions on magnetic flux density. The lower level identifies exposures below which, except in exceptional cases, it is considered to be safe, and which may be exceeded under controlled circumstances. Below this level, no biological effects have been observed in humans, although reversible effects have been noted on ECGs. The upper level identifies exposures which, present evidence suggests, it would be inadvisable to exceed. (Note that the IEC levels are slightly different.)

Further reading on this topic:
Books: MHRA Guidelines p25-26

« Back to Basic Physics question list

 
(This page: http://www.revisemri.com/questions/safety/static_field_limits_patients)