It seems that that the eml itself will not result in failure as it is not included in the list of mil's (malfunction indicator lights) that will result in failure, they are:-
Illumination of malfunction indicator light (MIL) for electronic power steering, electronic stability control, electronic park brake control, brake fluid warning lamp, tyre pressure monitoring system and air bag/preâ€tensioner/ load limiter
An eml (engine management light) should only normally attract an "advisory" which is what happened to a friend of mine recently, if you are still unsure then ring your MOT test centre and check directly Apparently there is some confusion as on some vehicles and EML can include one of the above MIL's
EDIT **B*gger** you guys beat me to it
Cheers Graham... at least you've given me more confidence as you're interpreting it the same as me.