If a coworker collapses while life guarding and shows signs of heat-related illness, what should be your immediate action?

When a coworker collapses while lifeguarding and displays signs of heat-related illness, aggressive cooling is essential because heat-related illnesses can progress rapidly and become life-threatening if not treated promptly. The body is unable to regulate its temperature effectively, leading to overheating, which can cause serious complications like heat exhaustion or heat stroke.

Immediately cooling the individual by pouring water over them, fanning them to promote evaporation, and applying ice packs to areas such as the armpits, groin, and back of the neck will help lower their core temperature more effectively than merely allowing them to rest and drink water. While hydration is important, it is ineffective as a first response in acute situations where the individual is in crisis. Calling for additional assistance, while a good practice for ensuring overall safety, does not directly address the urgent need for cooling. Performing CPR is critical only if the individual becomes unresponsive and shows no signs of circulation; it is not the initial step to treat heat illness. Therefore, taking decisive, immediate action to cool the affected person is the most appropriate response in this situation.