Government of Nova Scotia Government of Nova Scotia Nova Scotia, Canada


Petroleum Storage

Frequently Asked Questions

What is the largest cause of tank failures?

The leading cause for oil tank failure is corrosion which accounts for approximately 35 to 45% of tank failures reported to the department over the last several years. A good overview of the corrosion process in steel tanks can be found at, under Online Training.

What’s the difference between a 12 gauge and 14 gauge steel tank? Isn’t a 14 gauge tank thicker?

Actually, this is not the case. Gauge is the unit of measurement used when measuring steel thickness and a lower number means a thicker steel. However, manufacturers are now required to indicate the thickness of a steel tank in millimeters instead of a gauge value on their label in accordance with the latest edition of the Canadian Standards Association National Construction Standard for Aboveground Steel Tanks (CAN/ULC-S602-03).

My tank installer says that under latest version of the Canadian Standards Associations B139 Installation Code for Oil Burning Equipment, I can install my tank 2 feet from my furnace without any fire protection shielding in place. I always thought the minimum safe distance was 5 ft? Which is it?

True, under the 2004 edition of the B139, the required distance between the tank and the fuel fired appliance is 2 feet. However, the only recognized version of the B139 (as recognized by the Public Safety Division of Nova Scotia Environment and Labour) is the 2000 Edition. The 2000 Edition of the B139 specifies a separation distance of 5 feet. Until such time that the 2004 Edition of the B139 is officially adopted, the 5 feet separation distance applies unless fire protection shielding can be installed between the tank and the appliance.

I bought an old house that has fill and vent piping that exits the wall of the house. The thing is that the tank was removed years ago and both pipes are no longer connected to anything. Is this something I should be concerned about?

There have been several instances in the past where fuel deliveries have been made in error to fill pipes that were no longer connected to a tank resulting in a costly cleanup. The best course of action to take is to either permanently seal and label the fill and vent pipes as being abandoned or have them removed.

My tank always appears wet around the outlet piping but I don’t see any oil spots on the floor. Is this something to be concerned about?

Yes, this is a sign that the tank is “weeping”. You should have a service professional take a look at your tank as soon as possible before the “weep” turn into a costly leak.

Oil is expensive these days. Can’t I transfer all of the oil from my old tank to my new one?

The transfer of unfiltered oil from an old tank to a new tank should be avoided. Old oil, especially the oil sludge from the bottom of the tank contain bacteria and other contaminants which promote corrosion. New steel tanks are initially more susceptible to corrosion caused by the presence of these contaminants. Transferring these contaminants can result in premature failure of a steel tank in as little as eight months.