Ask the Rov: Can I fill up neggel vasser from a bathroom sink?
By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah
Shulchan Aruch rules that “one who leaves the restroom” is obligated to wash their hands. Poskim explain that this applies even if one merely entered the restroom without using it, due to the ruach raah (impure spirit) that rests there.1 Accordingly, the washing would need to take place outside the restroom.
Halacha discusses “Persian bathrooms” that were designed for the excrement and urine to immediately roll into a cavity at a distance to avoid a foul odor. Halacha rules that as long as there is no foul odor present, Shema may even be recited in the room.2
Based on this, some contemporary poskim posit that clean modern-day restrooms have a similar status. Yet often there is some dirt that remains in the toilet and there is a residual foul odor. In times of need, one may wash inside but recite the bracha outside.3 In this case, one should at least keep the hands wet and dry them outside the bathroom since some mekubalim hold that the drying is what drives away the impure spirits.4
If the bathroom has other uses — e.g. shower, laundry, storage closet — some poskim say that it may not have a ruach raah and are lenient not to require hand washing for merely entering. Yet there is still room to be stringent.5
What about to take water from the bathroom sink and use it to wash outside?
Some poskim permit using such water if needed to wash outside after using the restroom, and even to wash for bread. They hold that the impure spirit of a bathroom is less intense and doesn’t prevent one from reciting Hashem’s name in brachos. It also doesn’t transmit impurity to the food that one touches (like the impurity that rests upon one’s hands after sleeping).6
In his home, the Rebbe was particular about washing in the bathroom, or even taking water from the bathroom for negel vasser, unless the sink was separated by a sturdy curtain that wouldn’t wave in the wind or a doorway according to some.
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From The Weekly Farbrengen by Merkaz Anash