This image from a UK HSE publication may be the best image I have seen on “process safety” and Basic Process Controls Systems (BPCS). It shows how we PREVENT “overfill” events, also known as a Loss of Primary Containment (LOPC) event in atmospheric storage tanks/vessels.
The entire publication is a MUST-read for those who store flammable liquids in bulk ATM tanks. Never mind that it is from “across the pond”!
CLICK on the read more link below or visit the source for the full-size image.