[rprwhite]

I don’t think Aus/NZ would use it in this manner. It would be more likely to see “no dumping”.

[klondike_klive]

I remember going on a walk in London with my dad when I was little and we ended up in Hyde Park (this is late 1970s). There was a sign that said 'no dumping" which he chuckled at and explained to me the slang term 'dump', as in 'to defecate'.