“Drinking boiled water kāl” (Ukālelo pāṇī-no kāl) means: the fixed time-limit after boiling within which water may be drunk, so that new life (micro‑organisms) does not arise in it. This follows the Jain vow of ahimsā.

Essence

• Why: After some time, new jīvas can develop in stored water. Using it only within the kāl minimizes himsā.
• Never “extend” the kāl by mixing old and new water or by re‑boiling.

Common maryādā (practice)

• Śvetāmbara

- Monks/Nuns: Only boiled, filtered water within the maryādā set by Ācārya; generally boiled by day and used till next sunrise (one day, sunrise‑to‑sunrise). In stricter observances (e.g., Paryuṣaṇ, fasts), some follow a shorter limit such as one prahar (about 3 hours). - Lay followers: Commonly up to one day if properly covered and clean; during Paryuṣaṇ many keep the stricter maryādā.

• Digambara

- Monks/Nuns: Only boiled, filtered water; typically same‑day (sunrise‑to‑sunrise), with stricter limits in cāturmāsa as guided by the Saṅgh. - Lay followers: Often up to one day; stricter limits may be kept during Daśalakṣaṇa.

Basic rules to observe

• Boil in daylight, filter with a clean, dedicated cloth/strainer, store covered.
• Do not drink after the kāl has passed; discard the remainder.
• Follow the maryādā of your own Ācārya/Saṅgh; health exceptions are taken only under their guidance.

For simple explanations and community maryādā notes, see:

• Ukālelo pāṇī‑no kāl
• Kāla for boiled water in Paryuṣaṇ
• Why Jains insist on boiled water