- A chatzitza on the hand can disqualify the netilla if either it covers the majority of what must be washed or you don’t want the substance to remain on your hand. (MB 1)
- Lechatchila, inspect your hands before you wash. Even if you didn’t and you find a chatzitza after you washed, you can assume that the chatzitza came onto your hands after the netilla. (MB 1)
- You shouldn’t have long nails because dirt under the portion that extends longer than the finger is a chatzitza. Dirt under the nails opposite the skin is not a chatzitza even if it bothers you when you come to wash (if you didn’t care about it the whole rest of the day). (ShA 1 – MB 3,10)
- Dough or mud anywhere under the nails is a chatzitzah,unless it is such a small amount that people don’t normally care about. (ShA 1 – MB 6)
- There are two types of bandages:
- A bandage covering a wound that would hurt if you take it off. Since there is no worry that you would remove it during the meal, you do not have to wash the skin that is under it.
- A bandage covering some sore skin and does not hurt more when you remove it. There is a worry that you will take off the bandage in the middle of the meal, so you need to wash that skin. The bandage is a chatzitza. (MB 5)
- There is a dispute among the poskim in a case that you personally are not makpid on nail dirt, dough and bandages but most people are makpid. (MB 7,9)
- If most people aren’t makpid on a substance that you personally are makpid on, consider it a chatzitza. (Rama 1 –MB 10)
- You are allowed to clean under your nails on Shabbos (using your fingernails), just don’t scrape off part of your nail. (BeH “hu”)
- Some tradesmen get substances from their trade on their hands. If it is on a minority of the makom netilla it isn’t a chatzitza for them, since they aren’t makpid. Examples:
- Paint – painter
- Blood – butcher
- Fat – fat salesman
- Ink – scribe
For anyone else who is not a tradesman, the substance would be a chatziza. (ShA 2 – MB 12,13,14)
- A stain with no substance is not a chatzitza. (MB 14)
- A scab is not a chatziza if it hurts to pull it off. (Rama 2 – MB 16)
- If a woman removes her ring when kneading it is a chatziza for netillas yodayim. If a man would want to remove his ring when washing, so that the gem does not get dirty, it is a chatzitza. Such rings are chatzitzos even when loose. (B’dieved the netilla is valid if the ring was loose). Rings that you don’t remove are not chatzitzos even when tight. Just make sure you use a reviis over the hand wearing the ring. (ShA 3 – MB 18,19)
- There is a dispute whether you have to wash all the way up to the wrist or just the fingers until the palm. The minhag is to be machmir like the first opinion. If you don’t have a lot of water you may be maykil like the second opinion unless you have sweaty palms. (ShA 4 – MB 21,22)
- Since the minhag is to pour water up to the wrist, use a lot of water. A mere reviis might not cover every entire hand. Be very careful about this. (BeH “v’rouee”)
- In the event that you are washing only up to the knuckles, do not touch one hand to the other above the knuckles until you dry them. The space above your knuckles is still tomay and can transfer tuma through the droplets. (ShA Siman 162:7 – MB 56)