Dear Anshul
SAP is using at many places "identification listings" of different kind. E.g. for hit list, for composition/spec listing, hazard inducer etc.purposes. For DG filling in most cases a different ident listing is used. Now it depends on how do you use SAP. There is a "standard" ident. listing to be used for DG purposes; you need therefore to compare the different ident listings and may be adapt the set up.
Any SAP standard is starting with "D_" in customizing (e.g. D_HITLIST etc.):
C.B.
PS: e.g. check: Identification Listing
https://help.sap.com/saphelp_erp60_sp/helpdata/en/03/34981109d311d286e6080009b98822/content.htm
http://help.sap.com/printdocu/core/print46c/en/data/pdf/EHSDGP/LOEHSDGP.pdf