Question: What are the reasons for which it is permissible to break a salat?
ANSWER
They are as follows:
1. In order to kill a snake,
2. In order to catch a runaway animal,
3. In order to rescue a flock from wolves,
4. In order to take food that is boiling over away from the fire,
5. In order to protect your or someone else’s property from destruction,
6. In order to urinate or to break wind,
7. When there is no fear that the salat time may expire or
that you may be late for the jama’at, in order to rid yourself of
something that nullifies salat according to another madhhab,
e.g. to clean the impurity that is less than a dirham [a dirham is equal to 4 grams and 80 centigrams] or to make
wudu’ when you remember that you have touched a non-mahram woman, you can break your salat.

There are two reasons that make it fard [necessary] to break any salat:
1. Salat must be broken in order to save a person who screams for help, to save a blind person who is about to fall down into a well, to save a person who is about to burn or drown, or to put out a fire.

2. When your mother, father, grandmother, or grandfather calls you, it is not wajib, but permissible, for you to break a fard salat, yet you must not break it if it is not necessary. But voluntary salats [even the sunnat ones] must be broken. If they call for help, it is necessary to break a fard salat, too. If they call you knowing that you are performing salat, you may not break even a voluntary salat. But if they call you and do not know that you are performing salat, you have to break it.

Question: Is it permissible to break salat when the door is knocked or when the phone rings?
ANSWER
No, it is not permissible to break salat if there is no extreme necessity (darurat). It is haram to break salat in order to answer the phone. The person who knocks a door should wait at least for a time in which one can perform a four-rak’at salat.

Question: Scorpions enter our house from the garden. Sometimes they approach my prayer mat while I am performing salat. Is it permissible to break my salat to kill a scorpion?
ANSWER
It is permissible to break salat in case of danger. A hadith-i sharif says:
(Kill a snake and scorpion even when you are performing salat.) [Nasai]

It does not nullify salat and does not render it makruh to kill a snake or a scorpion that is moving closer to a person performing salat.

Question: If a non-Muslim comes and says “Teach Islam to me. I want to become a Muslim” while one is performing salat, will it be permissible to break the salat and teach Islam to that person?
ANSWER
Yes, it is permissible, but one must repeat the salat after it. (Fatawa-i Hindiyya)