SY Cabling - Current Carrying Capacity

Often I am finding SY used for the permanent fixed wiring of installations for circuits like Air Conditioning and Sockets. Apart from the obvious with SY Cable not permitted as such for these circuits as per BS 7671, Is there a specific current carrying capacity table for SY? This is because sometimes on EICR's we are finding SY being too small for the load but cannot always find the exact table/document to back this up.