Im curious to know whats the fine you would get from vosa If you where silly enough to put your tacho on a break and be working.?
I dont do this as I get paid by the hour and I enjoy my breaks 
Deliberate falsification of tachograph records = Level 5 fine of up to £5000 and/or 2 years in prison. They also usually suspend your licence for a period as well.
Thanks Coffeeholic