What is the consequence of having a combined chlorine level above the allowable limit?

Having a combined chlorine level above the allowable limit can indeed lead to an increased risk of swimmer irritation. Combined chlorine refers to chloramines, which are formed when free chlorine reacts with organic matter, such as sweat, urine, or skin cells. When these chloramines accumulate in the water, they can cause irritation to the eyes, skin, and respiratory system for swimmers. This is particularly problematic in swimming pools where chlorine is used for disinfection purposes.

Maintaining appropriate chlorine levels is critical for ensuring not only the effectiveness of disinfection but also the comfort of those using the pool. High levels of combined chlorine can also create a strong odor, which is often mistaken for high levels of free chlorine when, in fact, it indicates inadequate water treatment.

In contrast, the other options do not accurately describe consequences stemming from high combined chlorine levels. Excessive hardness and alkalinity in water are related to different chemical factors and not directly influenced by combined chlorine levels. The suggestion that there would be no specific consequence fails to acknowledge the known effects on swimmer health and comfort, making it essential for pool operators to monitor and manage combined chlorine effectively.