Q. I heard that Rav Shlomo Shlit'a does not permit wearing on Shabbos a raincoat with a hood, unless one is covering his head or hat with the hood. If left uncovered and there is no eruv, one would be liable for carrying on Shabbos . Is that true?
A. Poskim maintain that parts of a cloth that are permanently attached to it, or are attached to it in a way that it is not usually removed from it, one can carry them where there is no eruv, since they are considered part of the clothing.
Included in the above is the hood of a raincoat. (Oz Nidbaru 4:38; Piskei Teshuvos 301:31 footnotes 210 through 211, and others).
Horav Shlomo Miller's Shlit'a opinion is that if the hood is outside of the pocket of the raincoat, it is permitted to carry it, but not when it is stored inside of the pocket.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a