In some cases, committing fast invalidators does not invalidate fasting, and one is not required to perform the qada of fast. These cases are as follows. 1. When something other than liquids is taken in to the mouth and swallowed involuntarily, or when some water gets in to the nose and is swallowed involuntarily. 2. When in the month of Ramadan, one makes sure after investigating that the time for Fajr-Adhān has not arrived, and therefore commits acts which invalidate fasting, and later comes to know that it was Fajr time. 3. When one drinks water or eats something out of forgetfulness. 4. When one has a lawful courtship with his wife, while he is certain that it will not result in the discharge of semen from his body, but it is accidentally discharged anyway. 5. When one becomes junub on the night of Ramadan and goes to sleep, but he does not wake up until after Fajr-Adhān. 6. When water is entered in to the mouth to rinse out the mouth when performing wuḍū, and it is swallowed involuntarily. However, in cases other than wuḍū, if one knows that by rinsing out their mouth with water it will go down the throat, they should not do so. In general, rinsing out the mouth with water too much is makrūh for one observing fast, but if one performs this act, they should drive water out of their mouth afterwards. Therefore, it is advisable to drive water out of the mouth three times. In some cases, one is exempt from observing fast and one is not required to make up for it. These cases are as follows. 1. When one becomes insane at the time of time-specific obligatory fast, there is no qada of fast due on them. 2. A disbeliever who converts to Islam after puberty is not required to make up for the fast they missed at the time of disbelief unless a Muslim becomes an apostate and afterwards converts to Islam again, in which case they must perform the qada of the fast they miss when being an apostate. 3. One is not required to make up for the fast they missed while in coma. 4. If one becomes unconscious unintentionally, for example, if they are anesthetized for surgery, they are not required to perform the qada of the fast they missed at the time of anesthesia. But if losing consciousness happens intentionally, meaning without a legitimate excuse and due to taking some medication, based on precaution, they should make up for the missed fasts. 5. If the one observing fast becomes in toxicated, even if they have consumed the in toxicating material mistakenly or for treatment, their fast is invalidated and they must make up for it, even if one makes the intention to fast before becoming in toxicated and concludes the fast in a state of in toxication, they must still perform the qada of fast based on obligatory precaution.