Question : When does bleeding nullify the ritual ablution? What about bleeding from the nose? How do we tell whether the blood “flowed” or not and would this blood be considered pure or filthy?
In the Name of Allah, Most Merciful and Compassionate
Answer : The condition for blood [or other impure substances such as pus] to invalidate one’s ritual ablution (wudu) is that they:
a) exit the body; and
b) flow past the point of exit, actually or effective (such that if left unwiped, it would have flowed);
Further, anything that invalidates ritual ablution (wudu) is impure. [Multaqa al-Abhur] That which exits from the body without invalidating wudu is not impure, such as blood that appeared on the body surface but did not flow past the point of exit. [Multaqa al-Abhur, Tanwir al-Absar]
Nosebleed:
When blood flows down to the nose – even if only to the bony upper part – one’s wudu is broken. [Bada’i` (1.26), Hindiyya (1.11) quoting al-Muhit, Radd al-Muhtar (1.134) quoting Fath al-Qadir of Ibn al-Humam and al-Bahr al-Ra’iq of Ibn Nujaym]
However, if a clot of blood is found in the nose, it does not break one’s wudu. [ibid]
As for blood that comes out when blowing one’s nose:
a) if from a flowing wound in the nose, it breaks wudu;
b) if it flowed down into the nose, it breaks wudu;
c) if one sneezes and a clot of blood comes out, wudu is not broken—in order to break wudu, the blood needs to have flowed;
d) if one puts a finger into one’s nose, blood found on the finger will not break wudu, unless it was such that one is reasonably sure that it had flowed.