3,624. The Bracha on Separating Challah

Hilchos Bikkurim 5:11

Similar to the case in the previous halacha, if an adult kohein immersed in a mikveh and purified himself from a seminal emission or being a zav, he may eat this first challah. Outside of Israel, the one who separated it need not take a second challah. This is so even though the sun has not set (a necessary part of the purification process) and he is still unclean from corpse impurity.

Hilchos Bikkurim 5:12

One who takes challah recites the blessing that Hashem “sanctified us with His commandments and commanded us to take challah.” This is the case both in Israel and elsewhere. Just as we recite a bracha when taking ritually clean challah, we recite a bracha when taking ritually unclean challah. Therefore, a man may not take challah undressed because then he can’t recite the bracha. A woman who is sitting on the ground may take challah undressed and recite the bracha.