Is it permissible for a woman observing her iddah (waiting period) for the sun to set while she is outside her home, and does the ruling differ between a woman observing iddah for widowhood and one for divorce, and what is the ruling for a working woman observing iddah, such as a nurse at night?

A woman observing the 'iddah (waiting period) due to death or divorce must remain in the house where the 'iddah became incumbent upon her. She is permitted to leave during the day for a need and at night for a necessity. She must return to her home immediately once the need or necessity has been fulfilled. She is not allowed to spend the night outside her home except in case of necessity; for example, if she is a working woman who supports herself and her children, or a nurse for whom no replacement is available. When her task is completed, she must return to her home, because necessity is judged according to its extent. Ibn Qudamah said: "She is not allowed to spend the night outside her home, nor to leave at night except for necessity; because the night is a place where corruption is likely."