1. Washing or bathing, whether in cold or hot water is prohibited, even washing one’s finger is prohibited.

2. One may wash one’s hands if they are dirty, even in hot water, if necessary

3. Rinsing food is permitted, even if one’s hands will become wet.

4. Upon awakening in the morning, one may wash one’s hands taking care not to pour water above the joints at the end of one’s fingers.

5. After using the bathroom one is permitted to wash one’s hands (not above the joints at the end of one’s fingers). 

6. Before praying it is permissible to wash one’s hands (until the joints at the end of one’s fingers) only after using the bathroom or after touching parts of the body that are usually covered.

7. It is questionable whether or not a Kohen should wash his hands completely before Bircat Hakohanim, or just until his knuckles.

8. It is permissible to wash for medical reasons. 

9. One who must eat on Tishah B’Av should wash their hands completely.