How are storage tanks cleaned?

Both above ground and underground storage tanks require intermittent cleaning and checking for damage such as corrosion. But when do you need to think about cleaning your storage tank and how can it be done?

When to clean

If you’re due either an internal or external inspection of your tank, you will want it cleaned first. If you are changing its use from one type of liquid or gas to another, it will also need to be cleaned before the new substance can be placed inside. If the tank requires repair work it will also need to be emptied, cleaned and free of vapour before repair workers can safely enter the tank to carry out the necessary repairs. Do note that cleaning tanks always requires them being emptied first.

How to clean

Generally, storage tanks are cleaned by professional contractors who can do the job effectively and safely on your behalf. The first step is always to empty the tank completely by pumping or draining the contents. Then the electrical or mechanical components will need to be locked out. The tank will then need to be isolated from the system, which will entail the pipes to be drained also and where necessary fitting flanges to nozzle and pipelines and closing valves. The tank then needs to be mechanically vented in order to rid it of any dangerous gases and vapours. Any last remaining remnants of substance will need to be removed via either squeegee or vacuum. The entire interior including walls, floor and ceiling will then need to be power washed.


Sometimes during the course of cleaning or repairing a tank, issues may arise that mean the tank needs to be removed. As a result, this means that all of your storage tanks must have a decommissioning plan. The government issues strict guidelines when it comes to the decommissioning of tanks. Tank decommissioning should, therefore, only be performed by professional contractors who are experienced in this area, such as

As you can see, it’s important to have plans in place for the cleaning, maintenance, repair and decommissioning of all your storage tanks, both overground and underground. Cleaning storage tanks is vitally important for the safety of your staff and customers. Make sure you find a suitable firm to carry out your tank cleaning and decommission work.