Audit frequency thresholds revised for central excise and service tax, altering audit intervals and selection criteria. Audit frequency norms are revised to base selection on total duty payment (cash plus CENVAT credit) and to rebalance periodicity for Central Excise and Service Tax into four bands with annual, biennial, five year and proportionate-sample audit cycles. Selection within non-top bands uses unit-wise rupee risk calculations from DC (Audit) and local risk parameters; EOUs face a mandatory national sample prioritised by value of duty-free inputs and capital goods, with deviations allowed for local risk factors. The revisions take immediate effect, with first-quarter audits excepted.