What should be avoided by the one who wants to offer a sacrifice
When the new moon of Dhu’l-Hijjah appears, it becomes haraam for the one who wants to offer a sacrifice to remove anything from his hair, nails or skin.
عَنْ أُمِّ سَلَمَةَ رضي الله عنه أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ : إِذَا رَأَيْتُمْ هِلالَ ذِي الْحِجَّةِ وَأَرَادَ أَحَدُكُمْ أَنْ يُضَحِّيَ فَلْيُمْسِكْ عَنْ شَعْرِهِ وَأَظْفَارِهِ
Umm Salamah radi Allaahu 3Anha reported that the Prophet sallAllaahu 3Alayhi wa sallam said: “When you see the new moon of Dhu’l-Hijjah, if one of you wants to offer a sacrifice, let him refrain from (cutting) his hair and nails.” (1)
إِذَا دَخَلَتْ الْعَشْرُ وَأَرَادَ أَحَدُكُمْ أَنْ يُضَحِّيَ فَلا يَمَسَّ مِنْ شَعَرِهِ وَبَشَرِهِ شَيْئًا
According to another version: “When the ten days (of Dhu’l-Hijjah) begin, if one of you wants to offer a sacrifice, let him not touch his hair or skin with anything.”
The wisdom behind the prohibition on removing hair and nails is because the one who is going to offer a sacrifice is like the one who is in ihraam for Hajj and 3Umrah with regard to some rituals, which is the offering of a sacrifice in order to draw closer to Allaah. Thus some of the rulings of ihraam apply to the one who wants to offer a sacrifice, so he should not touch his hair and nails until he has slaughtered his sacrifice, in the hope that Allaah will release him from the fire of Hell.
It is not forbidden for him to wear new clothes or to put on henna or perfume, or to be intimate with his wife or have intercourse with her.
If a woman wants to offer a sacrifice:
Udhiyah is a confirmed Sunnah and is prescribed for both men and women. A woman may offer a sacrifice, whether her husband also offers a sacrifice or not.
If a woman wants to offer a sacrifice on her own behalf, whether she is married or not, then she should refrain from removing any hair from her body or cutting her nails, because of the general meaning of the texts which state that that is not allowed. No differentiation is made between men and women with regard to this ruling.
There are some women who delegate their brothers or sons to do the sacrifice on their behalf so that they can cut their hair during the first ten days of Dhu’l-Hijjah. This is not correct, because the ruling applies to the one who is making the sacrifice, whether he or she delegates someone else to do the actual slaughter or not. The prohibition does not apply to the person appointed, it applies to the person who wants to offer a sacrifice on behalf of himself, as is indicated by the hadeeth.
As for the person who is doing the sacrifice on behalf of another, whether because of a will or because he has been delegated to do so, the prohibition does not apply to him. (2)
Ruling About Combing the Hair before slaughtering for non-pilgrims:
Shaykh 3Uthaymeen (may Allaah have mercy on him) was asked: “What is the ruling about combing the hair in Dhul-hijjah before slaughtering the udhiyah for non-pilgrims?
He replied: “If Dhul-Hijjah starts and a person wants to sacrifice then he is not allowed to remove anything from his hair, nails or skin. But if a women needs to comb in these days and she wants to do slaughtering, then there is noting wrong with her combing her head/hair but comb lightly and if any hairs fall un-intended, then there is no sin upon her because she did not comb her hair to cut it but to repair it and the fall of hair happened unintentionally (she did not mean it).(3)
The family of the One Who is offering a sacrifice:
This ruling applies only to the one who is going to offer the sacrifice, and not to the rest of his family, and not to the one whom he appoints to slaughter the sacrifice on his behalf. None of these things are forbidden for his wife or children, or for his deputy.
And the Prophet sallAllaahu 3Alayhi wa sallam used to offer the sacrifice on behalf of the members of his household, and it is not narrated that he told them to refrain from that (cutting their hair and nails etc).(4)
Shaykh Ibn Baaz (may Allaah have mercy on him) said: “With regard to the family of the one who is going to offer the sacrifice, they are not subject to any obligations, and it is not forbidden for them to remove anything from their hair or nails, according to the sounder of the two scholarly views. Rather the ruling applies only to the one who is going to offer the sacrifice, the one who has bought the sacrificial animal from his own wealth.” (5)
Shaykh Ibn 3Uthaymeen said: “For the person on whose behalf the sacrifice is offered, there is no blame on him if he removes anything from his hair or nails. The evidence for that is as follows:
1 – This is the apparent meaning of the hadeeth, which indicates that the prohibition applies only to the one who is going to offer the sacrifice. Based on this, the prohibition applies only to the head of the household, not to the members of his family, because the Prophet sallAllaahu 3Alayhi wa sallam connected the ruling to the one who is going to offer the sacrifice, so what is understood is that this ruling does not apply to those on whose behalf the sacrifice is offered.
2 – The Prophet sallAllaahu 3Alayhi wa sallam used to offer the sacrifice on behalf of his household and it is not narrated that he said to them, “Do not remove anything from your hair or nails or skin.” If that had been forbidden for them, the Prophet sallAllaahu 3Alayhi wa sallam would have told them not to do it. This view is the more correct opinion. (6)
The scholars of the Standing Committee replied: “This hadeeth applies only to the one who wants to offer the sacrifice. As for the one on whose behalf the sacrifice is being offered, whether he is old or young he is not forbidden to remove anything from his hair, skin or nails, based on the basic principle, which is that these actions are permitted. We do not know of any evidence to the contrary. (7)
If the One offering sacrifice removes anything from his hair, nails or skin
If the person who wants to offer the sacrifice does remove anything from his hair, nails or skin then he has to repent to Allaah and not do it again, but he does not have to offer any expiation, and that does not prevent him from offering the sacrifice as some of the common people think.
If he does any of those things out of forgetfulness or ignorance, or some hair falls unintentionally, then there is no sin on him.
If he needs to remove it then he may do so, and there is no blame on him, such as if a nail breaks and it annoys him, so he cuts it, or if a hair gets in his eye and he removes it, or he needs to cut his hair in order to treat a wound and the like.” (8)
===================================================References: Main Source E-Book “Rulings on Udhiyah” by Shaykh Salih Munajjid: http://islamqa.com/en/ref/books/62 & Islamqa.com (1) Muslim (1977) (2) http://islamqa.com/en/ref/books/62 (3) Fatawaa Noor 3Alaa ad-Darb, cassette no. 283 (4) http://islamqa.com/en/ref/36567 (5) Fataawa Islamiyyah, 2/316 (6) In al-Sharh al-Mumti’ (7/530) [http://islamqa.com/en/ref/33743] (7) Fataawa al-Lajnah al-‘Daa’imah, 11/426, 427 [http://islamqa.com/en/ref/70290] (8) Fataawa Islamiyyah, 2/316 [http://islamqa.com/en/ref/36567