What technique can a lifeguard use to signal for help?

Using a whistle or siren is an effective technique for a lifeguard to signal for help because it produces a loud, clear sound that can travel over distances and easily attract attention. This method allows the lifeguard to communicate the need for assistance without relying on visual signals alone, which might not be noticed in a busy or chaotic environment.

In many scenarios, particularly those involving emergencies in a crowded pool area or beach, auditory signals like whistles can be more effective than visual signals because they can alert others even when they are not directly looking in the direction of the lifeguard. The use of a whistle has the added benefit of being a universally recognized signal for emergencies, prompting immediate action from nearby personnel or bystanders.

Other signaling methods, such as shouting or raising an arm, could potentially get attention, but they do not carry the same clarity and immediacy as a whistle. Waving a towel may draw some attention but is less effective in rapidly conveying an emergency situation. Swimming toward another lifeguard may delay the response time; instead, using a whistle allows for a more rapid call for help and keeps the lifeguard in place to monitor the situation.