Self Containment Certification
Self-contained vehicles must meet the Caravan Self Containment Certification standard. You'll need to be able to live in it for three days without getting more water or dumping waste. It must have:
fresh water storage
waste water storage, and
a rubbish bin with a lid.
A plumber or gasfitter needs to check if your vehicle meets the requirements. If it passes they will give you a warrant and sticker certification.