What percentage of tank fullness typically triggers an overfill alarm?

An overfill alarm is a critical safety feature designed to prevent the release of product from a storage tank during the filling process. The typical percentage of tank fullness that triggers this alarm is set at 90%. This threshold is established to ensure that the tank is monitored closely as it approaches full capacity, minimizing the risk of overfilling and subsequent spills that could lead to environmental impact or safety hazards.

Setting the alarm at around 90% allows for sufficient response time to stop the filling process before the tank exceeds its capacity. This proactive measure is essential for compliance with regulatory standards and helps protect both the facility and the surrounding environment. By triggering an alarm at this stage, operators can take necessary actions to prevent overfilling, such as stopping the transfer of product or adjusting the fill rate.

Other levels like 80%, 85%, or 95% might be relevant in specific contexts or operational procedures, but the 90% level is widely recognized and recommended for maintaining safety standards in tank management practices.