OFTEC Oil Storage Tank Regulations 4 — Questions and Answers
Question 1: What action must be taken before decommissioning an old oil storage tank?
- The tank must be emptied, cleaned, and rendered safe to prevent future contamination (Correct answer)
- It can simply be left in place with any remaining oil
- Only the fill point needs to be capped
- It must be buried in the ground
Correct answer: The tank must be emptied, cleaned, and rendered safe to prevent future contamination
Before decommissioning, the tank must be emptied of all oil, professionally cleaned, and either removed or rendered safe (e.g., filled with foam or sand). Residual oil and vapours in abandoned tanks are fire and environmental hazards.
Question 2: What is the recommended tank vent pipe arrangement for a domestic oil storage tank?
- A vent pipe terminating outside with a weatherproof bend, at least 600mm above the fill connection (Correct answer)
- A sealed cap on the vent connection
- The vent pipe should terminate inside a building
- No vent is required for tanks under 2000 litres
Correct answer: A vent pipe terminating outside with a weatherproof bend, at least 600mm above the fill connection
The vent pipe must terminate in the open air with a weatherproof bend (goose neck) to prevent rain entry. It should be at least 600mm above the fill point connection to prevent oil escaping during filling.
Question 3: When is a remote fill point required for an oil storage tank?
- When the tank cannot be safely accessed by the delivery tanker within the 30m hose length (Correct answer)
- Only for tanks over 5,000 litres
- Never — the fill point must always be on the tank
- Only for underground tanks
Correct answer: When the tank cannot be safely accessed by the delivery tanker within the 30m hose length
A remote fill point is installed when the delivery tanker cannot park within 30 metres of the tank or cannot safely access the tank directly. The remote fill pipe runs from the accessible fill point to the tank connection.
Question 4: What regulations specifically govern oil tank installations in Scotland?
- The Building (Scotland) Regulations and the Water Environment (Oil Storage) (Scotland) Regulations (Correct answer)
- Only English Building Regulations apply throughout the UK
- Scottish oil installations are unregulated
- Only EU directives apply in Scotland
Correct answer: The Building (Scotland) Regulations and the Water Environment (Oil Storage) (Scotland) Regulations
Scotland has its own Building Regulations and specific oil storage environmental regulations under SEPA (Scottish Environment Protection Agency). Requirements may differ from England and Wales on bunding thresholds and notification.
Question 5: What is the minimum clearance required between the bottom of an oil tank and the ground surface?
- Sufficient height to inspect underneath for leaks — typically the tank sits on a raised base or legs (Correct answer)
- The tank must sit directly on the ground
- At least 1 metre above ground
- 300mm minimum air gap
Correct answer: Sufficient height to inspect underneath for leaks — typically the tank sits on a raised base or legs
Oil tanks should be installed on a suitable base that allows inspection of the tank underside for leaks and corrosion. Many modern plastic tanks have integral legs or a plinth. The base arrangement must allow visual leak checking.
Question 6: What type of shut-off valve must be installed at the oil tank outlet?
- A fire-rated shut-off valve or an anti-siphon device (Correct answer)
- A standard gate valve is sufficient
- No valve is required at the tank
- A pressure relief valve
Correct answer: A fire-rated shut-off valve or an anti-siphon device
The tank outlet must have a shut-off valve and, where the tank is above the burner level, an anti-siphon valve to prevent the tank draining through a broken pipe. In fire-risk situations, a fusible fire valve may also be required.
OFTEC Oil Storage Tank Regulations 4
What action must be taken before decommissioning an old oil storage tank?