1. Before beginning Bedikaschametz (the search for chametz), one recites the following blessing: “Blessed are You, Hashem… Who has… commanded us concerning the removal of chametz.” And although the person will not be actually destroying the chametz until the morning, when it will be burned, nevertheless since the inspection is part of the process of destroying it. If the person did not recite the blessing prior to the inspection, he may recite it as long as he is involved in the search (Shulchan Aruch and Mishnah Berurah 432).
2. It is forbidden to speak between the recitation of the blessing and the commencement of the search. If one did talk, he must recite the blessing again. It is proper to not talk at all until the end of the search. However, it is permissible, without hesitation, to talk if it is for the sake of the search itself. Nevertheless, even if one did talk about unrelated matters, he does not have to recite a new blessing – as long as he did not talk between the blessing and the commencement of the search (ibid.).
