what invalidates it?

The following things are agreed upon as invalidating wudu:

1. Relieving oneself from the call of nature

2. Passing gas (breaking wind)

4.  Touching one´s private parts without barrier (i.e. cloth or the like)

5.  Menstruation and Post-partum bleeding (requires full bath: ghusl)

6.  Intercourse or emmission of sexual fluids. (requires full bath: ghusl)

After deep sleep or loosing consciousness it is advised to perform wudu, since one can not tell if one has broken wudu e.g. from passing gas or not.

Some scholars are also of the opinion that the following requires wudu:

1. vomiting

2. bleeding

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