Type D:

FIBC with electrostatic dissipative fibres protruding from the surface of the fabric to facilitate electrostatic charge dissipation into the surrounding of the FIBC via corona discharge.

Any conductive item that may not normally be grounded (e.g. drums on pallets) should either be grounded or removed from the vicinity of the FIBC.
The breakdown voltage is not exceeding 4 KV. Type D FIBC can be used in the presence of combustible dusts and in the presence of flammable gases or vapours.