The Anatomy of Self-Bunded Tanks

Business organizations that constantly require large volumes of petrochemical liquids or large volumes of fuel are putting themselves on a more advantageous position the moment they begin to use self-bunded tanks. Why so? It is because bunded fuel tanks are your best bet when it comes to the safe and reliable fuel storage solution. 

Basically, this type of storage tank for liquid fuel is just a tank within another tank. What makes them unique and remarkable is the fact that they are equipped with double steel walls,  features that allow for safe and effective containment of your high-value liquid, whether they be diesel, fuel, or petrochemical type.  

The gap of space between the inner and outer tank comes with a storage or containment capacity of 110% of the inner tank. The main purpose of this space found between the outer wall and the inner tank is to catch any leakage or spills, which is helpful in mitigating the likelihood of environmental contamination. 

When  Are You Required to Use a Bunded Tank? 

Practical applications of bunded fuel tanks can be seen usually in commercial and industrial premises. These organizations are the ones that usually require oil tanks with 200 liters storage capacity. 

Bunded fuel tanks are also required in domestic installations, where nestling of the tank should be carried out in accordance with the requirements of the local authorities. Tanks with 3,500-liter capacity need not have a bunding feature anymore. For instance, if you need to have a storage container sited in a geographic location where the occurrence of oil spillage is rather high and in close proximity to a body of water such as a lake, river or stream — you need to have a bunded tank installed here instead.  

If you are uncertain as to what type of storage tank you need to have, you may need to reach out to a local supplier first. These professionals can help carry out a risk assessment drill for you and eventually can let you know whether your current circumstances would necessitate you to have a bunded container tank or not. 

Additional Safety Features of a Bunded Tank

Apart from the “second skin” feature whose main purpose is to help prevent leakage, bunded fuel tanks come with several other features. They vary with respect to the model, make and size of the bunded oil tank. Typical standard safety features for this type of tank  include:

  • A tank gauge to help you assess the amount of fuel remaining in the tank. Will also indicate whether refueling would be necessary anytime soon or not. 
  • A lockable fill point. This is another security feature helpful in deterring fuel thefts.
  • A secure fuel inspection hatch allows you to access your the contents of your tank and clean it. 
  • An alert system provides you relevant  warning signals in any event that there is a  sudden drop in fuel  
  • An overfill protection device — as  the name of this device is suggesting it will grab your attention if the tank is about to 


When using bunded tanks to contain and store your high-value liquids, you will see that the level of security they are giving you will give you some peace of mind. These tanks have robust structures and their protective layering will help prevent the occurrence of damage to the surrounding area brought about by fuel leaks. 

Additionally, this “double layering” feature can help deter the incidence of fuel theft, one of the most complained about issues in the industrial sector. The extra wall feature makes it extra difficult for the would-be perpetrators to get through the inner section of the tank.