Shulchan Aruch Chapter 7:  The Law to Recite the Blessing of Asher Yatzar Whenever One Urinates (4 Paragraphs)
Note:  The Rama is in brackets [ ]

1.  Whenever one takes care of his needs, whether water or solid {1} he should say the blessing of Asher Yatzar (אשר יצר) but not the blessing of Al N'tilat Yadayim ( אל נטילת ידים ). This applies even if one wants to learn Torah or pray immediately {2}.  [If one got his hands dirty from wiping {3} with them, none-the-less, he does not say the blessing of Al N'tilat Yadayim {4}.]

2.  If one only passed water and did not get his hands unclean {5}, none-the-less he is required to say the blessing of Asher Yatzar אשר יצר.  One is not required to wash his hands in this case, but (should do so) because of cleanliness or because of preparation {6}.

3.  If one urinated and forgot about it, then one urinated a second time, he is required to recite Asher Yatzar (אשר יצר) twice.

4.  There is no minimum requirement for urinating; even a small drop obligates one to say the blessing of Asher Yatzar (אשר יצר).  For if that hole was closed up, blocking anything form coming out, this would be a tremendous problem, so one is required to give thanks to G-d.

{1} Lit. “Small or big
{2} This sentence may cause confusion, so let me clarify its intent.  The Shulchan Aruch stated previously that anyone who uses the rest room should wash his hands in the manner of N'tilat Yadayim.  However he is stating here that the blessing over this washing is not said in this instance. 
{3} Lit. “Rubbing”
{4} Again, one must wash his hands in the manner of נטילת ידים (N'tilat Yadayim) since his hands are unclean (both physically and spiritually) as the Shulchan Aruch stated previously.  However, one does not say the blessing. 
{5} Lit. “And didn't rub with them”
{6} I am unsure what “because of preparation” refers to.  Perhaps he means preparation for eating.  Alternatively, he is talking about preparing for praying or learning Torah and it is a sign of respect to wash your hands before praying or studying Torah.
Translated by Dr. Jay Dinovitser                          *This Page Was Revised and Corrected on 12/9/2009*
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