Activities That Require Netilat Yadayim
Netilat Yadayim is a ritual washing of one's hands. It is requires at certain points during the day including waking up, before a meal, and before davening. For those halachot, see the following pages: Netilat Yadayim upon Waking Up, Netilat Yadayim for a meal, Netilat Yadayim in preparation for Davening. For any other washing, see the details below.
Which Activities Require Netilat Yadayim?
- One should wash netilat yadayim after one:
- goes to the bathroom,
- touches one's shoes,
- touches one's legs,
- touches an area that usually covered,
- scratches one's head,
- enters a cemetery. 
- Whenever one touches an area of one's body that is generally covered must wash their hands.
- The upper arm of the arm that one puts on Tefillin isn't considered a covered area so if one touches it one doesn't need to wash netilat yadayim.
After Leaving the Bathroom
- The Shulchan Aruch (4:18) quotes from several rishonim that there is an obligation for one to wash netilas yadayim upon leaving a bathroom even if one did not relieve themselves. Many poskim hold no kli is necessary and neither is 3 times.
- The Gemara (Brachos 26a) describes a beis hakisei diParsai, which was a particularly clean bathroom because the waste would roll down to a pit a distance from the actual toilet, and therefore did not have some of the dinim of regular bathrooms. Modern poskim query whether our bathrooms should be treated like a beis hakisei diParai, and thus one would not require netilas yadayim upon exiting them, or not. The Chazon Ish (17:4) leaves this question in doubt, since unlike the bathrooms of the Parsai, in which the waste was removed immediately, our toilets hold the waste for a period of time until it is flushed away. Rav Shlomo Zalman Auerbach (Halichos Shlomo Tefilla 20:24), however, is lenient about this, and the Minchas Yitzchok (teshuva 1:60) concludes that in cases of need (bishas hadchak) one may be lenient not to wash upon leaving our bathrooms. Rav Schachter (Brachot Shiur 56 min 3-4) holds that there's no ruach raah in our bathrooms today.
- Ten Minute Halacha - Washing Hands After Bloodletting, and Cutting Fingernails, Hair by Rabbi Aryeh Lebowitz
- Yalkut Yosef 4:42
- Rashba 1:193 writes that whenever a person touches an area of one's body which is generally covered they must wash their hands because of the dried sweat (מלמולי זיעה) that gets onto one's hands. The same is true of a person who scratches their head.
- Does it apply if one's body is clean? Yafeh Lelev 1:4:22 writes that it seems from Shulchan Aruch that if a person's body is clean if he touched a covered area he doesn't need to wash his hands. His proof is Zevachim 19b. However, he concludes that the Mor Ukesiah 4:19 argues that even so they require netilat yadayim. (Mor Ukesiah is about feet but the Yafeh Lelev is applying him even to the other parts of the body.) Tzitz Eliezer 7:2:14 quotes the Yafeh Lelev 1:4:23 with respect to beard hair. Peninei Halacha cites this as well.
- Lev Chaim 2:5, the father of the Yafeh Lelev, asks whether touching one's feet requires netilat yadayim if they're clean. He proves from Zevachim 19b that during the kiddush yadayim and raglayim of the Kohanim that one doesn't need to wash one's hands after touching one's feet if they're clean. Yet, Ben Ish Chai in Rav Poalim 2:4 disagrees and answers that the ground of the Bet Hamikdash didn't have ruach raah. His opinion is repeated in Ben Ish Chai Toldot n. 1.
- Is there ruach raah on the feet? Mishna Brurah 4:41 writes that the reason for washing one's hands after touching shoes and feet is because they are dirty and not because of ruach raah. Ben Ish Chai in Toldot n. 17 agrees. Mor Ukesiah 4:19 assumes it is because of ruach raah.
- Is there ruach raah on the body? Bet Baruch 49b writes that there's ruach raah on the body and that isn't removed by washing one's body. Ben Ish Chai Toldot n. 1 and Rav Poalim 2:4 argues that there's no ruach raah with one's body, that's only relevant to one's hands and feet. Yabia Omer 5:1:5 agrees.
- Ben Ish Chai Toldot n. 17
- Amongst them the Mordechai in Brachos (194)
- Pointed out by Mishna Brurah 4:40. See Halacha Brurah (Otzrot Yosef 1:12) who discusses this question at length and cites the Magen Avraham 227:2 who implies that there's no obligation of Netilat Yadayim for just entering a bathroom but the Zohar holds that there is.
- https://www.ou.org/torah/machshava/tzarich-iyun/tzarich_iyun_washing_after_leaving_the_washroom/ quoting Yalkut Yosef v. 3 p. 96. He points out that there is a stringency to wash with a kli outside the bathroom but washing with a kli in the bathroom is pointless.
- As the Rabeinu Yonah quotes from Rav Hai Gaon on the Gemara in Brachos
- Rav Ovadia Yosef (Yachava Daat 3:1) wasn't lenient to wash in a bathroom in the morning before a meal unless there was no other option. Yalkut Yosef 4:84 extends this ruling both to washing before a meal and in the morning. Orchot Rabbenu 1:12 writes that in practice Rav Ovadia Yosef himself did wash outside a bathroom whenever he had to do netilat yadyaim including the washing after going to the bathroom. See the footnote for the discussion of the halacha.