Which flags indicate that swimming is prohibited?

The indication that swimming is prohibited is communicated through the use of red flags. In surf lifesaving and beach safety, a red flag signifies dangerous conditions for swimming, which might include rough surf, strong currents, or other hazardous circumstances. Lifeguards employ this flag to alert beachgoers and prevent swimming in unsafe waters, thus ensuring their safety.

The other flags convey different messages: blue flags typically indicate that swimming is allowed, green flags suggest safe conditions, and yellow flags serve as a warning of potential hazards while still allowing swimming. Understanding these flags is crucial for beach safety, as they are directly linked to the risk levels present at the beach.