In the presented situation, intending to turn right into a residential area do you have to signal this manoeuvre?

In the video you are driving along a housing estate street in a town, past houses and fences; ahead of you on the right there is a side street, next to which there is a blue sign D-40 "residential area". As you intend to turn right into the residential area, you must signal this manoeuvre. The answer is: yes.

The Road Traffic Act requires the driver to signal the intention to change direction or lane in good time and clearly, and to stop signalling immediately after completing the manoeuvre - turning into a side street is a change of direction, regardless of how that street is signed. Before turning right you move close to the right edge of the roadway and exercise particular caution, and when turning into an intersecting road you give way to pedestrians crossing the roadway you are entering and to cyclists going straight on. The Regulation on road signs and signals states that sign D-40 marks the entry to a residential area, where pedestrians may use the whole width of the road and have right of way over vehicles, the speed limit is 20 km/h, and speed bumps and other traffic-calming devices might not be marked with warning signs - that is why you switch on your indicator early and enter the zone itself slowly.

Legal basis: Art. 22 para. 2 point 1 and para. 5, Art. 26 para. 2, Art. 27 para. 1a, Art. 11 para. 5 and Art. 20 para. 2 of the Road Traffic Act (Prawo o ruchu drogowym); § 58 para. 1 and 2 of the Regulation on road signs and signals