In light of your experiences Martin, I'm thinking of printing out some health and safety guidelines on the back of my A4 wet slippy floor signs. I've never warned people in the past to beware of slippy carpets, but I think that that is now called for too. I'll be able to put as much info on this as I like and update it as necessary. I can give it to the customer and ask them to sign on the job sheet that they have recieved, read and understood the document.
Just as an aside, I've used a freshwater rinse with both OneStep and Spitfire Advanced. It is immediately obvious walking from the freshly cleaned carpet onto a hard floor that a detergent rinse is slippier underfoot than a freshwater rinse.
Safe and happy cleaning:)
Ken