Translation:Shulchan Aruch/Orach Chaim/75
75: To Be Careful of Exposed Hair and the Voice of a Woman at the Time of the Reading of the Sh'ma; and So, Not to Recite It in Front of the Nakedness. Contains 6 S'ifim.
1 If a handbreadth is uncovered on a woman in a place where her way is to cover it, even if she is his wife, it is forbidden to read the Reading of the Sh'ma in front of her. Gloss: And there are those who say: this is specifically with respect to his wife, but with another woman, even less than a handbreadth is considered nakedness (Hagahot Maimoni, Chapter 3). And it seems from the words of the Rosh that a handbreadth on a woman is considered nakedness even in regards to another woman, except that to herself she is able to read even though she is naked like was said earlier in Siman 44.
2
The hair of a woman that it is her way to cover is forbidden to read in front of it. Gloss: (Even his wife). But virgins for whom it is their way to go with an uncovered head, it is permitted.
Gloss: And so too is the law with the hairs of women that regularly come out of their covering (Beit Yosef in the name of the Rashba); and certainly foreign hair, even if it is her practice to cover (Hagahot Alfasi haChadashim).
3
One should be careful from hearing a woman's singing voice at the time of the Reading of the Sh'ma.
Gloss: And even with his wife. But a voice that one is familiar with is not considered nakedness. [Beit Yosef in the name of Ohel Moed and Hagahot Maimoni].
4 It is forbidden to read in front of "nakedness", even that of a heathen; and so too in front of the "nakedness" of a minor it is forbidden. [And there are those that permit in front of the "nakedness" of a minor so long as he is not considered capable of intercourse. Rabeinu Yerucham; the Rosh, Chapter "Mi Shemeito"; and Mahara of Prague]. And so is the main opinion. [See Yoreh Deah, Siman 265].
5 If there is "nakedness" behind a glass lamp and one sees it through its walls, it is forbidden to read in front of it, as is written, "and let Him not see anything unseemly among you", and here, it is seen.
6 If there was "nakedness" if front of him, and he turned his face from it, or closed their eyes, or it is at night, or he is blind, it is permitted to read for the Merciful One conditioned it on seeing, and behold he does not see it.