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505. A nÁsiyah can be of three types:
1. A woman who only had a habit of duration and has forgotten it. In this case, if she observes blood with the qualities of Îayà for not less than three days or not more than ten days, she should consider all of it as ÎayÃ. If it is for more than ten days, she should consider it as Îayà for as long as she entertains the possibility that it is ÎayÃ. If the (assumed) duration is less than six days, or more than seven days, she should combine the prohibitions of a ÎÁÞià with the obligations of a mustaÎÁÃah during the difference between the duration and six or seven days, a choice which is hers to make.
2. A woman who only had a habit of time and has forgotten it. In this case, if she observes blood with the qualities of ÎayÃ, and it is not for less than three days or more than ten days, all of it will be ÎayÃ. If the discharge is for more than ten days, and she knows that some of it coincides with her habitual days, she should combine the prohibitions of a ÎÁÞià with the obligations of a mustaÎÁÃah for the entire length of the discharge, even though all of the discharge or a part of it may not possess the qualities of ÎayÃ. The same will apply if she does not know, but entertains the possibility that it may coincide with her habitual days. If she does not entertain this possibility, and some of the blood possesses the qualities of Îayà and some of it istiÎÁÃah, and the blood with the qualities of Îayà is not discharged for less than three days or more than ten days, it will be considered Îayà and the rest istiÎÁÃah. If all of the blood possesses the qualities of ÎayÃ, or the part which possesses the qualities of Îayà exceeds ten days, she should treat it as Îayà for six or seven days, and istiÎÁÃah for the rest.
3. A woman with the habit of time and duration. This too can take on three forms:
a. She has only forgotten her habitual time. Her responsibility is the same as the one elaborated in no. 2 above, unless the blood possesses the qualities (of ÎayÃ) and she knows that it does not coincide with her habitual days, and it exceeds ten days. In this case, if her habitual duration is six or seven days, she should treat it as Îayà for that duration. However, if her habitual duration is more or less than that, obligatory precaution dictates that she combine the prohibitions of a ÎÁÞià with the obligations of a mustaÎÁÃah during the difference between that duration and six or seven days, a choice which is hers to make. She should treat it as istiÎÁÃah for the rest of the days.
b. She has only forgotten her habitual duration. In this case, the blood she observes starting from the habitual time for a period she is certain is not less than her habitual duration, will be considered ÎayÃ. As for the days exceeding this duration, if the blood possesses the qualities of ÎayÃ, and along with the aforementioned duration does not exceed ten days, all of it will be considered ÎayÃ. If it does exceed ten days, and the durations she conjures is the length of her habitual duration is less than six days, she should consider it as Îayà for that duration, and until the sixth or seventh day—a choice that is hers to make—she should combine between the prohibitions of a ÎÁÞià and the obligations of a mustaÎÁÃah. If the (probable) duration is more than seven days, it will be Îayà until the sixth or seventh day—a choice that is hers to make—and from the day of her choice (sixth or seventh) to the (probable) duration, which does not exceed ten days, she should observe the same precaution.
c. She has forgotten her habitual duration and habitual time. In this case, if the observed blood possesses the qualities (of ÎayÃ), and is not discharged for less than three days or more than ten days, all of it is ÎayÃ. If it does exceed ten days, and she knows that it does not coincide with her habitual days, and she conjures her habitual duration to be six or seven days, she should consider it as Îayà and the rest as istiÎÁÃah. If the (probable) duration is less than six days, she should consider it as Îayà for that duration, and until the sixth or seventh day—a choice that is hers to make—the obligatory precaution is to observe the responsibilities of a ÎÁÞià and a mustaÎÁÃah. If the (probable) duration is more than seven days, it is Îayà until the sixth or seventh day—a choice that is hers to make—and from the day of her choice (sixth or seventh) to the (probable) duration, which does not exceed ten days, the same precaution should be observed.
If the quality of the blood varies, some possessing the qualities of Îayà and some of istiÎÁÃah, the blood possessing the qualities of Îayà will be Îayà if it is not discharged for less than three days or more than ten days. As for the blood that was observed with the qualities of istiÎÁÃah, if she knows that it does not coincide with her habitual days, it is istiÎÁÃah. If she entertains the possibility that it coincides with her habitual days, she must act on precaution by observing the responsibilities of Îayà and istiÎÁÃah.