How does a tank inspection work?

First we unscrew the manhole cover, then we suck out the clean oil into a clean compartment in the car, the sludge is sucked into a sludge compartment. The inspector then steps down into the cistern, cleans and scrapes off surface rust and then checks the cistern visually and with ultrasound. We also review the function of other equipment. After reassembling the manhole, the tightness is checked with a weak air pressure and a tightness tester.

Now the inspection is complete and we refill the clean oil, then we issue an inspection report. If the facility is in operation when we arrive, we also check that it is before we leave. If an ID plate/address plate is missing, this is mounted.