Tayammum replaces wudu or ghusl when water cannot be found or cannot be used because of illness. The Quran says: if you do not find water, then seek clean earth and wipe your faces and hands with it (5:6). The Prophet ﷺ said that the earth was made a place of prayer and a means of purification.
1When it is allowed
No water is available after a reasonable search, or it is available only at a price that is beyond the person's means.
Using water would harm the person because of illness, a wound or severe cold, or would delay recovery.
The water that is present is needed for drinking, for oneself or for others, and there is not enough for both.
2How to do it
Make the intention to use it for the prayer or for the purification that is needed.
Strike clean earth with both palms (once in the hadith of Ammar), and blow off the extra dust.
Wipe the face, and then the backs of the hands, as in the hadith of Ammar.
3What cancels it
Everything that breaks wudu breaks tayammum.
Finding water, or being able to use it, before the prayer. If the water is found after the prayer, the prayer stands and need not be repeated.
Where the schools differ
The four Sunni schools agree on the main ruling above and differ in these points. No school is preferred here.
What is allowed to wipe with. the Hanafi school allows anything from the earth's kind, including stone and sand. The Shafi'i and Hanbali schools require earth with dust. The Maliki school allows anything on the surface of the ground.
The strikes and the arms. the Hanafi and Shafi'i schools say two strikes, with the arms wiped up to the elbows. The Hanbali school says one strike, wiping the face and the palms, as in the hadith of Ammar. In the Maliki school two strikes, with the wrists obligatory and the elbows recommended.
Wahai orang-orang yang beriman, apabila kamu hendak mengerjakan sembahyang (padahal kamu berhadas kecil), maka (berwuduklah) iaitu basuhlah muka kamu, dan kedua belah tangan kamu meliputi siku, dan sapulah sebahagian dari kepala kamu, dan basuhlah kedua belah kaki kamu meliputi buku lali; dan jika kamu junub (berhadas besar) maka bersucilah dengan mandi wajib; dan jika kamu sakit (tidak boleh kena air), atau dalam pelayaran, atau salah seorang dari kamu datang dari tempat buang air, atau kamu sentuh perempuan, sedang kamu tidak mendapat air (untuk berwuduk dan mandi), maka hendaklah kamu bertayamum dengan tanah - debu yang bersih, iaitu: sapulah muka kamu dan kedua belah tangan kamu dengan tanah - debu itu. Allah tidak mahu menjadikan kamu menanggung sesuatu kesusahan (kepayahan), tetapi Ia berkehendak membersihkan (mensucikan) kamu dan hendak menyempurnakan nikmatNya kepada kamu, supaya kamu bersyukur.
Wahai orang-orang yang beriman, janganlah kamu hampiri sembahyang (mengerjakannya) sedang kamu dalam keadaan mabuk, hingga kamu sedar dan mengetahui akan apa yang kamu katakan. Dan janganlah pula (hampiri masjid) sedang kamu dalam keadaan Junub (berhadas besar) - kecuali kamu hendak melintas sahaja - hingga kamu mandi bersuci. Dan jika kamu sakit, atau sedang dalam musafir, atau salah seorang di antara kamu datang dari tempat buang air, atau kamu bersentuh dengan perempuan, kemudian kamu tidak mendapat air (untuk mandi atau berwuduk), maka hendaklah kamu bertayamum dengan tanah - debu, yang suci, iaitu sapukanlah ke muka kamu dan kedua tangan kamu. Sesungguhnya Allah Maha Pemaaf, lagi Maha Pengampun.
From the Sunnah
Sahih al-Bukhari 335Authentic collection
The point of the hadith: The Prophet ﷺ said that the earth was made for him a place of prayer and a means of purification.
This is general information, not a fatwa. For your own situation, ask a qualified scholar.
Fiqh questions
Tayammum (dry ablution): when it is allowed and how to do it
Tayammum replaces wudu or ghusl when water cannot be found or cannot be used because of illness. The Quran says: if you do not find water, then seek clean earth and wipe your faces and hands with it (5:6). The Prophet ﷺ said that the earth was made a place of prayer and a means of purification.
Is this a fatwa?
No. It is a summary of well-known rulings with their evidence. For your own case, ask a qualified scholar.
What if my school differs from this answer?
Follow the view of the school you follow and the scholar who teaches you. The page lists the differences of the four schools.