What is a Bunded Oil Tank?
A bunded oil tank is simply a tank within a tank. This can be achieved in various ways and gets called many different things. This includes twin-skinned, double-skinned, and double-bunded tanks, to mention a few terms.
Why Do Oil Tanks Need To Be Bunded?
Oil tanks must be bunded simply because if the internal tank leaks, the fuel is contained within the bund.
An oil tank bund should be 110% bigger than the inner tank. In addition, the inner tank should be vented into the bund. If the inner tank is overfilled, the overspill goes into the bund rather than out onto the ground.
Oil tank bunding can be achieved by either a brick catchment area underneath the tank or purchasing a ready-bunded oil tank.
If you have a brick catchment area, this must be fully sealed so it retains liquids, and therefore water will build up inside, which should be removed by a licensed contractor. Below is a picture of an open bunded oil tank:-
Nowadays the most popular option is a ready bunded tank. Below is a picture of what a these tanks looks like inside:-
Bunded Tank Sizes
The inner oil tank is 100%, the outer oil tank only needs to be 10% bigger so that if the inner oil tank leaks, the fuel levels would be the same inside the tank and bund.
Steel & Plastic bunded oil tank materials are both available. They are both just tanks within tanks, completely sealed up so no water can get inside the bund. If the inner tank fails, the water goes into the outer tank rather than onto the floor.
Tank Lifespan
Bunded oil tanks usually last longer than single-skin tanks, and all come with a 10-year guarantee giving you peace of mind.
The Bunded oil tanks with a bottom outlet meet the regulations if permanently connected to an appliance (boiler or pump etc.) using steel pipework. However, you cannot use a bunded tank with a bottom outlet with a hose and nozzle on gravity to dispense into vehicles, as this does not meet the regulations.
Dispensing Fuel
For dispensing fuel into vehicles, the dispensing equipment must be contained within the bunded area if you have a hose off the end. If the hose were damaged, the diesel would drain onto the floor.
If you are dispensing fuel, you need a bunded oil tank with a pump mounted onto the top, like a fuel dispenser. Diesel dispensing tanks are available in both Plastic and steel.
Do You Need A Bunded Tank?
If you are putting in a new tank for oil at either your home or business, it should be bunded. All oil tanks in businesses should have been bundled by 2005.
When a tank for a domestic property is due for replacement, these tanks will also be required to be installed to the current regulations, with risk assessments being carried out. In addition, domestic properties will also require a bunded tank to be fitted.
Our staff have many years of experience in oil tanks and are very knowledgeable, give us a call on 01772 338892 with any oil tank enquiries you might have, and they will be happy to help you. Or send us a message through the website.
