Question about Kärcher Stone and facade cleaner RM 623

Hi Sergio,
It is legal to use. In the section “Specification” you will find a link to the safety data sheet that will answer your questions in all detail in terms toxicity and safety measures when you it. This is mandatory information to be supplied for those kind of products.
Personally I can confirm that is efficient and easy to use. The result on my terrace with and without the product is quite significant.