What does 2 whistle blows mean?
What does 2 whistle blows mean? A single whistle is used to catch someone's attention, but two whistles signal an emergency: someone is hurt or a child is missing. Three whistles means a water rescue, with a swimmer in distress.
What is the SOS whistle code?
Each whistle blast should last 3 seconds. Another important code is morse code of SOS which is three short blasts (3 seconds each), three long blasts (6 seconds each), and then another three short blasts (3 seconds each).