What method should lifeguards use to attract swimmers' attention?

The most effective method for lifeguards to attract swimmers' attention is through visual signals or using a whistle. This technique is crucial in a busy aquatic environment where there may be a lot of noise and distractions. Visual signals, such as raising an arm or using a flag, can quickly convey important messages to swimmers, especially if they are at a distance or if the lifeguard needs to signal a specific action, like "clear the area" or "come ashore."

Employing a whistle is particularly beneficial because it generates a distinct sound that can carry over water and through background noise, making it easier for swimmers to recognize that their attention is required. This method is non-invasive and helps maintain an orderly environment, ensuring that swimmers react promptly to important signals regarding safety or changes in conditions.

Other methods, such as yelling or throwing objects, are not as effective. Yelling can create confusion and lead to misunderstanding due to the loud, chaotic nature of a beach or pool setting. Throwing objects is only applicable in emergency situations and is not a standard method for attracting general attention. Therefore, using visual signals combined with a whistle stands out as the safest and most efficient approach for lifeguards to communicate with swimmers.