The importance of lifeguards providing patron surveillance, especially monitoring the behavior of swimmers, can be demonstrated with a brief description of how persons drown. Many people assume that drowning persons are easy to identify because they will exhibit obvious signs of distress in the water, such as yelling or waving their arms. However, this kind of behavior is not common. Instead, people tend to drown in more quiet, less attention-getting ways. Drowning persons usually struggle to keep their mouth above the surface of the water in order to breathe. Struggling to stay afloat and possibly suffocating, they are rarely able to call out or wave their arms. Observational studies of persons at flat water (non-surf) beaches have revealed that non-swimming adults who find themselves in water over their heads are generally able to struggle on the surface of the water for about 60 seconds, while infants and very small children can submerge in as little as 20 seconds. However, facility owners and managers at aquatic facilities sometimes make the mistake of assigning lifeguards unrelated duties to perform while also expecting them to conduct effective patron surveillance. Because drowning can occur quickly and quietly, it is not surprising that lifeguards, distracted from keeping an eye on the water by other assigned duties, have failed to spot drowning persons in time to rescue them. Indeed, unobserved drownings have occurred even while lifeguards were stationed 20 feet from the incident. It is clear, therefore, that swimming facilities must be staffed adequately to ensure effective and continuous patron surveillance, and that lifeguards should be given no other task that would distract them from this work.