OFTEC Oil Storage Tank Regulations 2 — Questions and Answers
Question 1: What type of base is required for a plastic oil storage tank?
- A level, non-combustible base extending 300mm beyond the tank on all sides (Correct answer)
- Any flat surface including wooden decking
- The tank can be placed directly on grass
- A raised platform at least 1 metre high
Correct answer: A level, non-combustible base extending 300mm beyond the tank on all sides
Plastic oil tanks require a firm, level, non-combustible base (typically a concrete slab) that extends at least 300mm beyond the tank footprint on all sides. This prevents settlement, provides stability, and offers fire protection from ground level.
Question 2: What is an integrally bunded oil tank?
- A tank with a built-in secondary containment wall forming a tank-within-a-tank (Correct answer)
- A tank surrounded by a separate brick wall
- A tank with double-thickness walls
- A tank with an alarm system built in
Correct answer: A tank with a built-in secondary containment wall forming a tank-within-a-tank
An integrally bunded tank has the secondary containment built into its construction — essentially a tank within a tank. This eliminates the need for a separate bund wall and is popular for domestic installations where space is limited.
Question 3: What is the minimum distance an oil tank must be from a non-fire-rated building if a fire barrier wall is NOT installed?
- 1.8 metres for a plastic tank (Correct answer)
- 0.3 metres for any tank
- 5 metres for any tank
- No distance is required for steel tanks
Correct answer: 1.8 metres for a plastic tank
Without a fire barrier, a plastic oil tank must be at least 1.8 metres from a non-fire-rated building. Steel tanks require 1.0 metre. These distances can be reduced with an appropriate 30-minute fire-rated barrier wall.
Question 4: What must be installed on the oil supply pipe where it passes through or under a building?
- A fire valve externally and the pipe must be in a protective sleeve (Correct answer)
- Nothing special is required
- Only a filter
- A pressure relief valve
Correct answer: A fire valve externally and the pipe must be in a protective sleeve
Where an oil supply pipe enters or passes under a building, a fire valve must be installed on the external side. The pipe should also be sleeved where it passes through walls or floors to allow for thermal movement and leak detection.
Question 5: What device should be installed on the fill point of a domestic oil storage tank?
- An overfill prevention device (such as a tank gauge or electronic alarm) (Correct answer)
- A pressure relief valve
- A fire valve
- A flow meter
Correct answer: An overfill prevention device (such as a tank gauge or electronic alarm)
An overfill prevention device is required to prevent the delivery driver from overfilling the tank. This can be an electronic gauge with alarm, a mechanical float gauge, or a whistle vent that changes tone as the tank fills.
Question 6: What is the fire separation distance for a steel oil storage tank from a non-fire-rated building?
- 1.0 metre minimum (Correct answer)
- 1.8 metres minimum
- 3 metres minimum
- No separation required
Correct answer: 1.0 metre minimum
Steel oil tanks require a minimum separation of 1.0 metre from a non-fire-rated building, compared to 1.8 metres for plastic tanks. Steel tanks are more fire-resistant, hence the reduced distance requirement.
OFTEC Oil Storage Tank Regulations 2
What type of base is required for a plastic oil storage tank?