When are cabin crew allowed to pour liquids into galley and lavatory sinks?

Cabin crew are never allowed to pour liquids into galley and lavatory sinks at any time during a flight operation. This policy is in place primarily for sanitation and operational integrity reasons. Allowing liquids to be poured down these sinks could lead to plumbing issues and create hazardous waste management situations.

While there might be situations in ground operations where other forms of liquid handling are acceptable (such as for cleaning), specifically pouring liquids into these sinks is not permitted. This ensures that the aircraft remains compliant with safety regulations and maintains hygiene standards for both the crew and passengers.