a) Ensure bulk above ground storage facilities conduct and document a risk assessment that
takes into account the following factors:
1. The existence of nearby populations and sensitive environments;
2. The nature and intensity of facility operations;
3. Realistic reliability of the tank gauging system; and
4. The extent/rigor of operator monitoring
b) Equip bulk aboveground storage containers/tanks with automatic overfill prevention systems
that are physically separate and independent from the tank level control systems.
c) Ensure these automatic overfill prevention systems follow good engineering practices.
d) Engineer, operate, and maintain automatic overfill prevention systems to achieve appropriate
safety integrity levels in accordance with good engineering practices, such as Part 1 of
International Electro-technical Commission (IEC) 61511-SER ed1.0B-2004, Functional
Safety – Safety Instrumented Systems for the Process Industry Sector.
e) Regularly inspect and test automatic overfill prevention systems to ensure their proper
operation in accordance with good engineering practice.