3.Those who have only the habit of duration.

492. Woman having this kind of habit are three types:

First, a woman whose duration of Hayz in two consecutive months is same but the commencing times differ. In such circumstances her habit of duration will be the number of days during which blood is seen. Fore example, if blood is seen from the 1st to the 5th of the 1st month and from the 11th to the 15th of the 2nd month her duration habit will be 5 days.

Second, a woman who does not become Pak from blood, but for two consecutive months, some days she sees signs of Hayz and other days she sees signs of Istihaza, and the number of days that shows signs of Hayz is equal in each month, but its time is not the same, in this case, all days that has the signs of Hayz, will be considered as her habit. For example, if one month she sees signs of Hayz from 1st to 5th and the next month she sees it from 11th to 15th and afterwards she sees the signs of Istihaza, her habit days are 5 days.

Third, a woman who sees blood in two consecutive months for 3 or more days, and then it stops for a day or two before it starts again, though the time of commencement of blood varies in the 2nd month from that of the 1st, her duration habit will be the number of days during which blood s seen, provided that the total number of the bleeding and Pak days does not exceed ten and that the duration period in both the months remains equal, provided that it s not totally more than 8 days, her habit will be 8 days.

493. If a woman with the fixed habit of duration sees blood for more days than her habitual duration, and it exceeds 10 days and the nature of blood remains same throughout, then she will calculate her habitual duration from the day bleeding began, and treat it as Hayz. But if the nature of blood changes, with some days showing signs of Hayz and others showing signs of Istihaza, then there can be three possibilities:
If the number of days in which blood shows signs of Hayz tallies with the habitual duration, then she will take those days as of Hayz, and the rest as Istizala; if the number of days in which blood shows signs of Hayz exceeds her habitual duration, then she will take her habitual duration as Hayz, and the rest as Istizala; if the number of days in which blood shows signs of Hayz is less than her habitual duration, she will add some days to complete her duration and take that period as Hayz, and treat the rest of the days as of Istizala.