question #3 Sahih al-Bukhari 341, Book 7, Hadith 8 : What are the conditions under which tayammum can be performed according to Islamic teachings?

`Ammar said to `Umar “I rolled myself in the dust and came to the Prophet (ﷺ) who said, ‘Passing dusted
hands over the face and the backs of the hands is sufficient for you.’ ”