If you store diesel, oil or chemicals on site in South Africa, containment is not optional. The rule most operations get wrong is the capacity calculation — and it is the one an inspector checks first.
The 110% rule
The governing standard for above-ground fuel storage and bunding in South Africa is SANS 10089-3. The core requirement is straightforward:
A bund must hold at least 110% of the volume of the largest tank within it. Where multiple containers share a bund, it must hold 110% of the largest tank or 25% of the total volume of all containers — whichever is greater.
The extra 10% is headroom for rainwater and firefighting water, so the bund does not overflow at exactly the moment you need it.
Worked example: five 1,000 L IBCs in one bunded area. 110% of the largest is 1,100 L. 25% of the total 5,000 L is 1,250 L. You must design to 1,250 L — the greater of the two. Sizing to 1,100 L because that is what the biggest tank calls for is the classic mistake.
What the bund itself has to be
- Impermeable to the product stored. Reinforced concrete, or lined with a membrane rated for fuel or the specific chemical.
- Structurally sound. It has to hold the liquid load without failing.
- Free of uncontrolled drains. A bund that drains to stormwater is not a bund. If it has a valve, it stays closed and locked, and someone owns the decision to open it.
When is a spill pallet enough?
Spill containment pallets are accepted for temporary storage — drums and IBCs staged in a warehouse or workshop rather than a permanent bulk installation. The working expectation is that each pallet can capture the contents of at least one full drum placed on it.
So the sizing logic carries over. A 4-drum pallet holding 205 L drums needs a sump of at least 205 L, not 205 L divided across four. You are containing one failure, not a share of one.
Where a spill pallet is not enough:
- Permanent bulk storage above the thresholds in SANS 10089-3
- Outdoor storage where rainwater ingress will fill the sump and displace capacity
- Anywhere your environmental authorisation or municipal by-law specifies engineered bunding
Outdoor storage and rainwater
A sump full of rainwater has no spare capacity. Outdoors you need either a cover or a managed drain-down procedure — inspect, confirm the water is uncontaminated, release, close and lock. Undocumented, that procedure is the thing that turns a spill into a finding.
Practical compliance checklist
- Capacity calculated as 110% of largest or 25% of total — take the greater
- Bund or sump material compatible with what is actually stored
- No open drain to stormwater; valves closed, locked and owned
- Spill pallets sized to one full drum, not a fraction
- Rainwater managed on anything outdoors
- Spill kit sized to the largest credible release, stored where you can reach it
- Inspection routine written down and signed off
Get the standard, do not rely on a summary
This page is a working orientation, not a compliance certificate. Requirements shift with volume, product classification, site zoning, your environmental authorisation and municipal by-laws. Before you build or sign off an installation, read SANS 10089-3 in full and confirm the specifics with your local authority or a competent environmental practitioner.
Equipment
We stock the containment side of this: spill containment pallets, IBC totes and bulk containers, steel drums, plastic drums and chemical tanks — every unit priced upfront with live stock status.
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