BS7671: What are the requirements for caravan electrical hook ups (EHU)? - Bing video
Does it really matter?
And.......are modern caravans really "large metal boxes" these days? Or are they more of an electrically insulating large glass fibre (G.R.P.) covered frame with few touchable metal parts?
Also, should their metal chassis and internals really be bonded, does that really increase safety?
We see few, if any, real metal covered caravans like this in the U.K.
https://www.bing.com/videos/search?q=youtube+airstream+caravan&docid=608025708304140408&mid=60AAF07E4E57C782FD0E60AAF07E4E57C782FD0E&view=detail&FORM=VIRE
Z.