C-H, Thanks for your explanation.

>but what do you use in Belgium? Please tell me you use type B for sockets! Do you use 20A or 16A for them, BTW?

In belgium we have a TT system (in residential installations) and therefore use type C curve. We use the radial system (as you understood) and we use 2.5mm2 wire/cables with a max value if breaker being 20A. All sockets have to be with ground.