At what turbidity level must swimming pools not exceed during peak bather load?

The correct turbidity level that swimming pools must not exceed during peak bather load is 1.0 NTU (nephlometric turbidity units). This standard is established to ensure that the water remains clear enough for safety and hygiene purposes. Maintaining turbidity at or below this level allows for effective monitoring of water quality, enabling better visibility of swimmers and any potential contaminants in the water.

At 1.0 NTU, the clarity of the pool water is sufficient to ensure that any hazards, such as pool drains or swimmers in distress, are visible. Higher turbidity levels can obscure visibility and may indicate the presence of microorganisms or contaminants that can pose health risks to swimmers.

In general, turbidity levels that are lower than 1.0 NTU are preferred; however, during peak usage, it’s crucial to have clear visibility and water quality assurance at this specific threshold.