Will this device not create a "faecal aerosol effect" for want of a better way of putting it?
No. Because the OP knows better.
Very entertaining thread. Enjoyed it immensely.
JBR, the water regulations are there to provide protection for all of us and have to be based on a worst case scenario. It is true that under normal circumstances there would be no backflow through your Shatoff. If however, the water supply becomes de-pressurised due to being shut off or leakage, a reverse flow could happen.
The contents of toilet bowls are classed as the most severe, category 5 contamination and therefore carry the most stringent backflow prevention requirements. It is not enough to say that you would keep the spray head clean and not leave it dangling in the bog. However unlikely, there are circumstances where the spray head could end up in contaminated water.
A lot of domestic plumbing, including showers, contravenes regulations either because its old or installed by people who don't know or care. This does not mean that we can disregard the regs in the future.
No-one on here can stop you doing what you like in your own house but we have to advise that you do things correctly. If you have the attitude that the regulations should not apply to you because you are not the idiot they were designed for, you will get the comments you deserve.
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