As with all insurance policies, home insurance and oil spill insurance really only cover the accidental, the unexpected and the hard to mitigate. You can reduce the risk of a claim by making sure your tank is complaint and secured. New integrally bunded tanks are the best way to avoid oil spills altogether, as the outer container will catch all of the oil in the inner container should it leak.
Providing oil supply pipes are continuous, i.e. without joins, the only weak points are the connections either end, both of which are easy to access and monitor.
In all cases, an annual inspection by an Oftec registered engineer will identify any weaknesses and recommend remedial and maintenance works.
For more on the current requirements for oil tanks, try our Guide to Oil Tank Regulations