Utilization of cenvat credit

Basically Rule 6 is meant for those who manufacture both dutiable and exempted goods with the common duty paid inputs. The thumb rule of central excise is that you can utilise the cenvat on inputs only if your final product is dutiable. Rule 6 lays down the rules to maintain seperate accounts of the inputs used in the manufacturing of dutiable and non dutiable goods. But sometimes it is not possible to maintain seperate accounts. For such cases Rule 6(3) is given. So rule 6(3) is basically there to save this thumb rule.