Similar to the nautical Beaufort scale which measures wind, the Beaufart scale measures the stink of farts, from 1 to 9 - 10 or above is always a follow through, which normally means stinks like fuck.
In the library Kevin leaned over on his chair, looked around and did what he thought was a silent but deadly
, deadly it was - 2 pensioners shuffling past were stopped in their tracks. One of the pensioners turned to Kevin and said " Fuck me boy, that trouser cough of yours is worthy of a 7.1 on the Beaufart scale
. "Thank you" said Kevin "My previous best was only a 5.3"