David W.E. Roberts wrote:
Is there a British Standard Turd (BST)?

There is! Although is been flattened by the european one now.
Annex F of BS EN 997 gives details of 'test specimens'
Also the ability to flush 20g of fine sawdust spread evenly round the bowl.

From DEFRA -
"When tested as described in Clause 11, for the first six flush cycles, or
for a minimum of eight out of ten flush cycles, each of the four test
specimens shall be completely evacuated from the WC bowl and pan's outlet.
The recorded after-flush volume in each flush cycle shall be no less than
40% of the full flush volume."

--
Toby.

'One day son, all this will be finished'