For your own health avoid these vans.
- firstly I have to ask why do you need to 'wash' paving stones?
- secondly it's not just water it is soap as well?
- thirdly if you are doing it do you have to repeatedly have to bang into the fencing time and time again just to make sure I am paying attention.
Sounds dangerous I wonder if it melts rubber tyres? also it's not wet because they have just been washing the floor it's just rained which seems to have done a pretty good job of washing and cleaning?