This guide has been written to provide guidance relating to the requirements for the certification of offshore containers with a gross mass not exceeding 25,000 kg (55,116 lb), intended for repeated use to, from and between fixed or floating installations and ships. These containers may not always conform to the standard design requirements of the International Convention for Safe Containers (CSC). Accordingly, some of the features that differentiate offshore containers from the containers that are designed according to the CSC are indicated below.