The set-points for overfill alerts should not exceed what percentage of capacity?

The correct answer is 90% because this value serves as a safety threshold designed to prevent overfilling of the tank. Setting the overfill alert at 90% capacity allows sufficient margin for any fluctuations, ensuring that there is always enough space in the tank to accommodate the contents and prevent spillage. This is crucial for environmental safety and regulatory compliance, as overfilling can lead to potential leaks, groundwater contamination, and significant regulatory penalties.

By keeping the overfill alert at a maximum of 90%, operators can effectively manage tank levels and respond proactively before reaching a critical overflow situation. This practice aligns with industry standards and regulations that prioritize safety and the prevention of environmental hazards.

In contrast, setting the alert at higher percentages, such as 95% or 100%, may compromise safety. These higher percentages increase the risk of overfilling since there is less room for error, making it more likely that a tank could overflow before the alert is heeded. Therefore, maintaining an overfill alert set-point at or below 90% is essential for safe tank operations.