For decades, aquatic safety professionals have wondered why unconscious victims so often are recovered from pool bottoms by patrons rather than trained lifeguards. While it has been easy and sometimes lucrative to blame the guards for not being vigilant and professional, recent evidence suggests it may not be their fault. In fact, average, everyday swimmers may have a physical and visual advantage over even the best-trained and most vigilant lifeguards.

To date, the “recognition, intrusion, distraction factor” has been most often used to suggest that guards on duty are negligent when an unconscious person is not detected in a timely fashion. While the RID factor may be accurately applied when there is a surface struggle, what explanation can be appropriately used when there is no surface struggle?

Though short, subtle and silent surface struggles have been know to occur, many victims begin and end their troubles on the bottom without a struggle or detection. Many drowning victims can be described as “plunge downers.” These individuals dive, slide or jump into deep water and simply fail to surface. They often remain at or near the bottom because they are complete nonswimmers, or they succumb to sudden cardiac arrest or arrhythmia that may be induced by genetic “drowning triggers.” Shallow-water blackout is another deadly recipe that begins on the bottom.

When a surface struggle does occur, most experts agree that it is shorter rather than longer. If the motions on the surface are minimal, and the lifeguards do miss it, detecting the body under the surface of the water is far more difficult. In many cases, bottom detection may be impossible.

In attempting to ascertain what takes place visually when bodies rest on the bottom, my colleagues and I spent much of 2005 filming what lifeguards actually see in a variety of pools. To do this, we placed video cameras in the lifeguard chairs and focused on child manikins on the bottom while the surface water was still quiescent. Then, with clear footage of the manikin on the bottom, we waited for natural surface agitation to begin.

To our amazement, the slightest surface disturbance in the pool — whether caused by other swimmers, inadvertent splashing or simply the wind — often distorted the view of the victim. In many cases, the video, aptly titled “Disappearing Dummies,” revealed that the bodies underwater were like jigsaw puzzles that were completely pulled apart as surface agitation and turbulence increased. This phenomenon occurs in all bodies of water, natural and artificial. Even under the best of conditions with crystal clear water, bodies beneath the surface are difficult to detect. When filming the manikins in this study, turbid water, glare and obstructions did not exist. In some cases, darker bodies on white pool bottoms simply disappeared. The 10-minute video clearly illustrates how difficult it is to detect bodies underwater with just the human eye. Unlike a clear glass window that perfectly still water presents, surface water that is disturbed creates an obscuring window by means of reflective angles and edges that prevents penetrating vision below.

So now we know why swimmers in the water often recover bodies on the bottom of pools — rather than it being done by lifeguards on duty. Swimmers eliminate the reflective angles on the surface by having their faces just below the surface. Goggles enhance this visual advantage further. Hence, the popularity of snorkeling, scuba diving, glass-bottom boats and aquariums.

Many lessons emerged from our experiment:

1 Whenever surface disturbance exists, it is extremely difficult if not impossible to see objects clearly under the surface. All the training in the world cannot enable lifeguards to see what is impossible for them to see.

2 Underwater video and, better yet, computerized drowning detection systems are needed to reveal what is below the surface. If these technologies cannot be obtained, guards may be required to scan the bottom while in the water wearing masks or goggles.

3 Guards must be taught to respond immediately to any unusual shadows, smudges or dark objects below the surface, without hesitation. When in doubt, fish it out.

4 The bottom of the pool, not the surface, must be prioritized during visual scanning. An unconscious victim on the bottom should have priority over a struggling, still conscious victim on the surface. As Jill White in her Star Guard program emphasizes, “Water quickly hides, then suffocates.” Likewise, Ellis and Associates has been performing “dummy drops” to test its guards since 2001. And the YMCA mentions scanning from the bottom up. Unfortunately, the majority of guards in this country are still trained to prioritize the surface even though distressed swimmers and even potential drownees on the surface have a timely advantage over those already on the bottom, “running on empty.”

5With the growing popularity of breath-holding competitions and underwater distance swimming, many more deaths will occur needlessly unless we ban prolonged breath-holding activities and teach lifeguards to pull people up from the bottom regardless of the circumstances.