The time for Tayammum (When can one do Tayammum ?)
A person in need of bathing or ablution must do “Tayammum” if he is incapable of using water. Some important conditions of performing “Tayammum” are as follows:
There should be no sign (or knowledge) of water being available for a distance of at least one mile, in all the four directions.

An illness that would get severely aggravated or get prolonged upon using water. This could be the person’s own judgment from experience or the opinion of a pious reliable doctor.

The extreme cold which could cause the person to die or fall ill if he takes a bath, and no warm blankets are available to keep out the cold after bathing.

The danger of missing the train or bus etc., if he alights from it in order to use water.
Danger of missing the Fajr (Dawn) Prayer or the congregational Prayers of Eid.

Method and some important rules regarding Tayammum
Three things are obligatory in “Tayammum”

  1. Making an intention (Niyah) that the particular “Tayammum” is for ablution or for bath or for both.
  2. Passing soiled palms over the entire face, not leaving out a single spot equal to the breadth of a hair.
  3. Passing soiled palms over both arms up to and including the elbows, not leaving out a single spot equal to the breadth of a hair.

At first, make an intention and after reciting “Bismillah Shareef”, strike the hands on any solid matter which is related to the earth i.e. soil, mud, stones, marble, or any such thing upon which is considerable dust. If the hands get soiled with too much dust, strike the base of one thumb upon the base of the other to loosen it. Then pass both hands over the entire face, not leaving out even a single spot equal to the breadth of a hair. The area around the lips which remains exposed in the natural state when the mouth is closed should also be covered in this “Masah”. If the person is bearded, he should then run his fingers through the beard.

Strike the hands again on the soil. Now perform “Masah” of the right arm, by placing the inner portion of all fingers, except the thumb, on the outer portion of the right arm. Pass the left-hand fingers over the fingertips of the right arm up to the elbow. Coming back from the elbow pass the palm over the inner side of the right arm up to the wrist. Then do “Masah” of the right thumb using the inner side of the left thumb. Similarly, repeat the entire process for the left arm.

While striking the palms on the soil or mud, the fingers must be kept open. If dust has reached between the fingers, “Khilaal” should be done (by rubbing other fingers between them). If the palm had been struck on stone or other such things by which dust does not reach between the fingers, then ‘Khilaal’ becomes obligatory.

Women should take extra care during “Tayammum” by moving ornaments (such as rings) in order not to leave the area below them – whereas nail polish should be totally removed.

If cold water is harmful to sickness, warm water should be used if available. If warm water is unavailable, “Tayammum” should be done.

If any portion is covered by a bandage (or plaster) because of an injury, then “Masah” with wet hands should be done over such bandage – and the rest of the body washed as usual with water. If pouring water does not cause harm, water should be poured over such a bandage. In due course, if it is not harmful to do “Masah” over the injured part, “Masah” should be adopted immediately. Later when washing the injured portion will not cause harm, it will become obligatory to wash it. It should therefore be understood that when the ability exists, the superior act must be performed and the lesser act will no more suffice.

If very little time is left for offering Prayer, and it is feared that the time will lapse if one takes a bath or performs ablution, one must perform the “Tayammum” and offer the Prayer. It is however incumbent to repeat such Prayer after proper bathing or ablution.

If the excuse due to which “Tayammum” was done does not remain anymore, it will make the “Tayammum” invalid. The occurrence of anything that breaks the ablution will also break the “Tayammum” which was done in place of ablution. Similarly the occurrence of anything which makes bathing compulsory will break the “Tayammum” which was done in place of bathing.