After eating, drinking, sleeping, travelling, touching hairless lips, changing clothes, discharging semen, urine and faeces, uttering slang words, spitting, before beginning studies,after entering into courtyard or crematory a Brāhmaṇa (Brahmana) should perform punarācamana (act of washing of face, hands and legs once more). That is, if Ācamana is performed in both morning and evening, punarāya (punaraya; again) or further Ācamana should be done. Speaking to Caṇḍāla (Chandala), Mleccha, Strī (Stri; woman), Śūdra(Sudra) or ucchiṣa (ucchista; something that has come in contact with cooked food, or remaining food after the meal), touching any ucchiṣa person or ucchiṣṭa  food , while bleeding or shedding tears, and before eating Ācamana is to be done. Even after bathing in the both junctures of the day Ācamana is due after urination. Ācamana should be done after sleeping too. After touching fire, cow or Gaṅgā(Ganga)-water,  Ācamana is needed. on touching a female body, wearing blue clothes, dropped hair from own body, unwashed clothes, one should touch pious water (water for purification) , wet grass or earth. Seating with the face to the north or east, being saṃṁyatavāk ( in a reticent mode). Ācamana should be performed with foamless/ frothless /nonfrothy normal (not warm) water. Impurity persists when Ācamana is done for washing the legs with a covered head, neck, being muktakaccha (portion of the loin cloth hanging loose instead of remaining tucked at the back of the waist in between one’s legs) or muktaśikha (one with unknotted tuft of hair on his head)

Ācamana should not be done wearing shoes, staying in water or putting on a turban on the head. During gossiping, laughing, looking to and fro/ hither and thither, going to bed, overlooking the hair etc. with water Ācamana is prohibited. Ācamana should not be done with ucchiṣṭa water given by a Śūdra or an unholy person or with a little quantity of water that comes on a finger tip. One should not make a noise or not be inattentive during Ācamana. Ācamana is forbidden with such water that is impure, with colour and flavour, or stirred water. A Brāhmaṇa gets purified when the Ācamana-water reaches to the heart,
; a Kṣatriya(Kshatriya) gets purified when it reaches to the throat, a Vaiśya only when it enters into the mouth, and a Female as well as a Śūdra by a simple touch to the tongue edge. A Brāhmaṇa should always perform an Ācamana with water of Brahmatīrtha. Brahmā, Viṣṇu and Maheśvara are satisfied with water that is drunk thrice in an Ācamana. Gaṅgā(Ganga) and Yamanā are pleased when mouth is cleaned with the aṅguśṭhamūla ( root of the thumb) after an Ācamana. Candra (Chandra; the Moon-god) and Sūrya (Surya; the Sun-god) are gladdened by touching the eyes. Touching the nāsāputa (Nasaputa; nasal septum) makes the twine Aśvinīkumāra(Aswinikumara) satisfied. All the deities are delighted by the touch of the heart. On touching the head Parama-puruṣa (the Almighty) becomes highly pleased.

The body does not become unholy on falling of the very small drops of water from the mouth during Ācamana. Things attached tooth is treated same as tooth. By a sudden touch of anything or taking any other thing in hand, if a Brāhmaṇa becomes ‘unholy’, then he will be purified again by throwing the thing on the earth followed by an Ācamana.

Ācamana is of six kinds — Śuddha (Suddha), Smārta (Smarta), Paurāṇīka (Pauranika) Vaidika , Tāntrika (Tantrika), and Śrauta (Srauta). Cleansing after evacuation of bowels and urination is called Śuddha Śauca (Suddha Saucha). After Śauca, one needs to perform Smārta and Paurāṇika Ācamana  as per rules. Vaidika and Śrauta Ācamana are due at the place of Brahmayajña(Brahmayajna) and so forth. Tāntrika Ācamana is prescribed in actions like learning or practicing lessons of weaponry.