NHMRC has developed a guide for researchers and administrative staff on what constitutes Direct Costs of Research. This guide was approved by Research Committee in December 2010. The intention of the guide is to assist Administering Institutions in ensuring that only costs that are integral to the approved research objectives of a grant (i.e. direct research costs) are incurred during the approved funding period.
This guide is available on the NHMRC website under Direct Research Costs.
If further assistance is required then clarification should be sought from NHMRC.