Chapter Fourteen Al HaShulchan page 38-39
5. If his tallit fell off him unintentionally and he wishes to put it on again, if it fell off completely there is a difference of opinion if he needs to recite the blessing therefore he puts it on without a blessing; if most of the tallit fell off but some still remained on him then all agree that he does not recite another blessing. (v.Sh.Ar. ibid. and K.Hach ibid.58)
Note from us: Please consult your own rabbi to find out what to do - these are for learning purposes only.
As quoted from:
Shulchan HaMelech, a Kitzur Shulchan Aruch in 3 volumes as compiled by Maharan HaRav Shmuel Laniado z'al, 1923 with the supplement "Al HaShulchan" containing various opinions compiled by Ezra Basri, Chief Justice of the District Court, Jerusalem in 1992.
We would like to dedicate this learning for the speedy and complete recovery of several people, including Gittel bas Yehudis, Mendel ben Florence, our friends' 5-year-old son, Joseph Benjamin, son of Ireneusz Khrystof, diagnosed in April with ALL leukemia, and a longtime friend of the family, Franco, son of Joseph, who is B"H recovering from thyroid surgery. Please have them in mind when studying. For updates on Joey please go to his site, http://caringbridge.org/visit/josephlacki
B"H we did our last Happiness Conference Call Thursday night on skype, reading the Rabbi Pliskin Happiness book as a merit for these and other cholim - we thank those who participated and hope you will all join us for the next installment Tuesday night at 9pm (contact me to find out how to join - email@example.com)