If, and a big if in weather like we are having, the van is cool inside and the dog(s) dont bark or howl, I dont see it should be a problem. On rare occasions we have left them for up to 6 hours when we are home, so apart from the heat why should it be any different in a van?. I hate to see dogs, large and small, dragged round shops, shows etc. they cant possibly enjoy the experience, especially when it is very hot.
This weekend, we had all windows/skylights open and blinds drawn, including windscreen covered. it was cooler in the van than outside. It was a C &CC rally so it was possible to do this, not so safe on a commercial site.
I think perhaps a lot of sites have a 'no dogs to be left in vans' policy to prevent yapping, barking, howling, whining dogs - not all dogs behave like this - thank goodness!
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