This document specifies test methods for the determination of the plastics compatibility of packaging/ intermediate bulk containers (IBC) made from polyethylene, fluorinated polyethylene and coextruded plastics. It covers the determination of adequate plastics compatibility against the processes of deterioration: softening due to absorption (swelling); stress cracking; and combinations thereof. It applies to: drums and jerricans made from plastics; composite packaging (plastics) with inner receptacle made from plastics; rigid plastics IBCs (types 31H1 and 31H2); and composite IBCs with rigid plastics inner receptacles (type 31HZ1); used for the transport of liquid dangerous goods. This proof of adequate plastics compatibility is only applicable to the above packaging and IBC types of the following materials and material specifications: packaging and IBCs made from polyethylene (PE)1); packaging and IBCs made from polyethylene (PE)1), whose internal surfaces are fluorinated; and packaging and IBCs which are coextrusion blow moulded and have walls with the following multilayer structure (from inside to outside): polyamide (PA)//bonding agents//polyethylene (PE), or ethyl vinyl alcohol (EVOH)//bonding agents//polyethylene (PE).