T’vul Yom 4:2

A woman who is a t’vul yom (technically, a t’vulas yom) may knead dough, cut challah from the dough, separate it, place it on an Egyptian basket or on a board, bring it near (the main dough) and designate it as challah. This is because it only has third-degree impurity, which is considered ritually clean when it comes to chulin.

T’vul Yom 4:3

If a kneading trough is a t’vul yom, one may knead dough in it, cut challah from the dough, bring it near (the main dough) and designate it as challah. This is because it only has third-degree impurity, which is considered ritually clean when it comes to chulin.