Short answer
The Hanafi school has two types: heavy impurity (ghalizah), such as urine, stool, blood and wine, excused up to the size of a dirham; and light impurity (khafifah), such as the urine of cattle and horses, excused below a quarter of the garment or limb. The Shafi'i school, followed in Malaysia and Indonesia, uses three: mughallazah, mutawassitah and mukhaffafah.
Najasah ghalizah up to a dirham does not invalidate the prayer: for a liquid, about the area of the hollow of the palm; for a solid, the weight of a mithqal. Exactly a dirham must still be washed (praying with it is makruh tahrimi), less than that should be washed (sunnah), and more than that must be washed for the prayer to be valid. Najasah khafifah is excused if it covers less than a quarter of the garment or limb.
Other madhhabs
- Shafi'i
- Three types: mughallazah (dog and pig, washed seven times with soil once), mukhaffafah (a milk-fed baby boy's urine, sprinkled) and mutawassitah (everything else). Only small amounts are excused, such as specks the eye cannot see and a little blood.
- Maliki
- Impurity is not graded the same way; less than a dirham of blood is excused.
- Hanbali
- Small amounts of blood and pus are excused, other impurities are not, and impurity is washed seven times.
Explanation
Hanafi heavy impurity (najasah ghalizah) includes human urine and stool, flowing blood, pus, a mouthful of vomit, semen, madhy, wine, pork, a dog's saliva, the droppings of chickens and ducks, and the urine and droppings of animals whose meat is not eaten. Light impurity (najasah khafifah) includes the urine of animals whose meat is eaten, like cows, sheep, goats and camels, the urine of horses, and the droppings of birds of prey. The droppings of birds that are eaten and fly, such as pigeons and sparrows, are pure.
How much is excused in prayer (Hanafi):
- Heavy: prayer is valid with up to a dirham on you. An amount equal to a dirham must still be washed, since praying with it is makruh tahrimi; less than that should be washed as a sunnah. More than a dirham must be washed before you pray.
- Light: less than a quarter of the garment or the limb it is on.
- Tiny specks of urine, like the points of needles, are excused.
The Shafi'i types, often searched as najis mughallazah, mutawassitah and mukhaffafah:
- Mughallazah (heavy): dog and pig. Washed seven times, one of them with clean soil.
- Mukhaffafah (light): the urine of a baby boy under two who has had only milk. Sprinkling water over it is enough.
- Mutawassitah (medium): everything else, such as urine, stool, blood and vomit. Washed until colour, smell and taste are gone.
Shafi'i books also speak of najis ainiyah (impurity you can see, smell or taste) and najis hukmiyah (dried impurity with no trace left), which is purified by running water over it once.
The Hanafi rule on a baby's urine is stricter: see baby urine and vomit. For cleaning methods see cleaning najis from clothes.
The evidence
Quran, Surah Al-Muddaththir 74:4
وَثِيَابَكَ فَطَهِّرْ ﴿٤﴾
And your clothing purify
The general command to keep clothes pure.
Sunan Abi Dawud 376
Grading to be checked... يغسل من بول الجارية ويرش من بول الغلام ...
"A baby girl's urine is washed, and a baby boy's urine is sprinkled."
The basis of the Shafi'i light category; the Hanafi school reads sprinkling as a light wash.
Where the ruling is recorded
- al-Hidaya, Kitab al-Taharat, chapter on impurities and their purification. Heavy impurity is excused up to a dirham and light impurity below a quarter.
- Radd al-Muhtar (Ibn Abidin), Kitab al-Taharah, chapter on impurities. Measuring the dirham by area and by weight, and which impurities are heavy and light.
- Minhaj al-Talibin, Kitab al-Taharah, chapter on impurity. The Shafi'i categories and seven washes for the dog and pig.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.