The portion of the head to be wiped over in Wudhoo’
26-8-2015 | IslamWeb
Question:
If I am in a public place and have to perform Wudhoo’ (ablution), could I enter my hand under the hijab in order to wipe my head and ears, even if water reaches only the front of the head?
Answer:
All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The scholars unanimously agree that wiping over the head in Wudhoo’ is obligatory. Allaah Almighty says (what means): {And wipe over your heads.} [Quran 5: 6] However, they provided different views regarding the portion that is to be wiped. Some scholars are of the view that the whole head should be wiped, and others said that it is sufficient to wipe only a part of it. The preponderant opinion, however, is to wipe the whole head because the Prophet 
used to do so. ‘Abdullaah ibn Zayd, may Allaah be pleased with him, described the Wudhoo’ of the Prophet saying: "He wiped over his head with his hands. He passed his wet hands over his head starting from the front up to the back and then brought them back to the same place from which he started." [Al-Bukhari and Muslim]
This action of the Prophet is an explanation of the command mentioned in the verse, and the explanation takes the same ruling of the command, which is the obligation of wiping the head.
Consequently, you are required to wipe the whole head and it is not obligatory to pass the hands back and front. It is only a description of the way of wiping the head and it is recommended according to most of the scholars.
A woman making Wudhoo’ in a public place contradicts the command of Allaah; to be screened from people’s eyes. That is because unveiling the face, hands and feet in order to wash them in Wudhoo’ is unavoidable. So she has to perform Wudhoo’ in a place where non-Mahram (permanently unmarriageable) men cannot see her. This will enable her to perform Wudhoo’ in a perfect way, including wiping over the whole head, just as we indicated earlier.
Allaah Knows best.