How many pool users can a lifeguard supervise in unprogrammed sessions?

GUIDANCE

This article examines how many pool users a lifeguard can safely supervise in unprogrammed sessions, sometimes known as the lifeguard-to-pool user ratio. 

 

How many pool users can one lifeguard supervise in an unprogrammed session? 

UK industry guidance does not specify the number of pool users a single lifeguard can supervise in an unprogrammed session. 

 

How many pool users would it be appropriate for a single lifeguard to supervise in an unprogrammed session? 

A court may take into account the following when determining the appropriate number of pool users a lifeguard could supervise effectively: 

• the maximum pool occupancy. 
• the factual circumstances surrounding the incident. 
• any relevant industry guidance. 
• any published research. 
• the approach adopted by pools in similar circumstances. 

Factors that might contribute to the factual circumstances surrounding a particular incident may include: 

• the admissions policy. 
• the control the operator has over who is admitted to the pool. 
• the characteristics of the pool users in the session. 
• the session type taking place. 
• the view of the lifeguard on duty. 
• any reports made by lifeguards requesting additional lifeguard cover. 
• the quality of the results and methodology adopted in the operator risk assessment. 
• incident records containing preventable incidents if additional supervision had been provided. 

Operators are best advised to remain within known operational practices (i.e. those shared with other operators) when setting their own lifeguard-to-pool user ratios for unprogrammed sessions. There is often safety in numbers regarding a litigation safety net. 

 

How many pool users is typical practice in the industry? 

RLSS UK has for over two decades included references in their manuals to 1:30 being used as a starting point, which is found in other international lifeguard manuals and the research literature. I am unaware of the origin of this recommendation. Still, in any event, the scant UK industry literature on the subject over the last twenty years is likely to render any original study of limited use. 

To my knowledge, there has never been a study of Normal Operating Procedures to understand the typical practice for UK pools regarding the maximum number of pool users a lifeguard thinks they can safely supervise. 

 

What is an inappropriate number of pool users for a lifeguard to be asked to supervise? 

My answer to this question is any number of pool users where the lifeguard is unable or fails to meet the minimum standard of supervision expected of a lifeguard. Again, it is not a practical answer to that question, but it remains the most likely yardstick against which an operator's choice will be judged. 

For more information on the minimum standard of supervision and examples of situations where the standard might be said not to be met, see our article on the standard of supervision. 

 

What academic research is there on this topic? 

Academic experimental studies have explored the relationship between detection rates and the number of pool users. Unfortunately, the findings are often secondary outputs of the research and not the principal aim of the study. The studies are typically small in scale, and most involve detection exercises on a computer rather than on a real-life pool surround. 

The US National Lifeguard Survey 1995 received 2,796 responses across 34 states and a roughly equal (52:48, male:female) gender balance. Griffiths, Steel, and Vogelsong (1996) reported one of the study's findings that 60% of lifeguards were often responsible for 50 or more pool users in their zone. It is unclear whether this meant they were solely responsible for 50 pool users or shared this responsibility with another lifeguard. Harrell's 1999 study into four Canadian indoor swimming pools also found that lifeguard scanning deteriorated as pool user numbers increased. 

Laboratory studies have repeatedly demonstrated that searching through very large displays is difficult and extends the average time required for positive detection (e.g. Wolfe, 1998a, cf. Neider & Zelinsky, 2008). However, insight into lifeguard attention and the effect of boredom has presented the hypothesis that pool user numbers may have a relationship that is more "bell-curve" in shape than the straight line presented by a positive correlation. Our anecdotal collection of swimming pool incident records supports this hypothesis.

More research is undoubtedly needed, and any relationship is likely to be influenced by individual and environmental factors other than attention and lifeguard capability to supervise a certain number of pool users. 

 

References

Griffiths, T., Steel, D., and Vogelsong, H. (1996). Lifeguarding behaviors. A century of safety? Parks and Recreation, Arlington. 31(2), 54. 

Harrell, A. (1999). Lifeguards' vigilance. Effects of child-adult ratio and lifeguard positioning on scanning by lifeguards. Psychological Reports. 84(1), 193-197. 

Neider, M. and Zelinsky, G. (2008). Exploring set size effects in scenes: Identifying the objects of search. Visual Cognition. 16(1), 1–10.

Wolfe, J. (1998). What can 1 million trials tell us about visual search? Psychological Science. 9, 33–39. 

 

Citation: Jacklin, D. 2022. How many pool users can a lifeguard supervise in unprogrammed sessions? Water Incident Research Hub, 30 January.