How is anybody on here supposed to answer the question without knowing more about the scanner? Power output? Why not ask the supplier/manufacturer of the scanner, who will have the technical details and product knowledge and the likely risk that you have mentioned.

If he is OK, then he got away with it. You need to find out the magnetic field pattern around the scanner and find out what the vertical distances are to the 5 gauss line. It is almost certainly fine, as these machines are often in multistorey buildings. The people who set up the machine (i.e. the in-house staff) will almost certianly have this information. The axis of a body scanner magnet is generally horizontal and the exclusion distance is likely to be symmetrical, so the exclusion distance perpendicular to the axis is likely to be the same in all directions (i.e. to the sides, underneath and over the top). The 5 gauss line is usually used to prevent danger to people with implants such as pacemakers. The danger from flying objects kicks in a little closer to the magnet.

Pardon me if this is a silly question but is the MRI scanner room lead lined? I do know some of these scanners have lead lined walls, ceilings, doors and special glazing. If so there is no problem as that lining is designed to prevent anything escaping from the room.

He should contact his UNISON health and safety rep as soon as possible this person has been radiated with magnets and that is serious a claim is not for compensation its to prevent it happening to others in the future Had he been a CT scanner this would need immeadiate reporting to the NHS, only if the field goes from the room it should not as it will have radiation absorbing material in the roof lining. As it’s an MRI scanner and its magnetism there is no problem. The risk in an MRI scanner is noise the persons have to wear ear defenders, it is that loud. Followed by flying objects or moving metal, thats why you cant go in the room with a pacemaker , not that it will stop , its because the sensor wire may move --walking through the field has no adverse effects, Lead does not stop magnetism , there is no substance on earth that is a magnetic isolator, so the lobes are reduced and channeled ,so that leakage will be minimised I once witnessed a screw driver fly from an electrician’s hand working in the room under a scanner from about 18 inches and he could not get it off the ceiling, He should have read the signs and used phozzy bronze screwdrivers

You can shield to a degree, see this material https://en.wikipedia.org/wiki/Mu-metal

Cant beat a good inverse square law where you have to multipy the power by a factor of 16 to double the range..

Inverse square laws don't work well for things that are not point sources. An MRI machine is not a point source.

Might also be worth considering that MRI scanners use such powerful magnets that they have to be cooled with liquid Helium; any leakage of this will result in the escape of Helium gas, which being lighter than air will gather at the highest point i.e the ceiling. Apart from instantly gaining the ability to talk like Donald Duck, anyone at this level risks asphyxiation.

Off subject but i remember a time when people actually had manners. Cant abide arrogant know it alls who dont understand the meaning of the word polite.

Actually i never meant you haha...i probably should have kept my thoughts to myself but am having a bad day and fancied a rant :)

How child like.

Not my problem! After several episodes in an MRI scanner (I'm still here) I conclude that short term biological effects are nil (but I have no tattoos) for me. The operator is in the same area, albeit several metres remote from me (and no screen). Compare that to a recent HRCT scan, where the operators were in a heavily screened area...and red lights were on and the doors secured. Reading between the lines I conclude that of greater risk to the patient, in an MRI scan, is the high-power rapidly-varying RF fields (up to 400MHZ)....mention has been made that localised heating in heavily-tattooed areas may be a large hazard. On the roof is irrelevant to RF because the MRI scan area is usually screened to RF anyway.. Still, not to worry.....here is an risky sorta data thingy.... http://www.willis.com/do...afety_August_2009_V6.pdf I would not worry much about MRI effects on roof climbers....I've been exposed to non-ionising radiation of several kilowatts many times over the years, and that has not damaged me....although I notice a tendency to howl during a full moon...and I also note that the noise inside the coil is absolutely deafening, even with ear plugs.

All of which SHOULD be the responsibility of the contractor/employer. "HEALTH AND SAFETY RISKS IN MAGNETIC SHIELDING DESIGN AND CONSTRUCTION FOR MAGNETIC RESONANCE IMAGING (MRI) SUITES " http://researchrepositor...pository_16_Feb_2012.pdf