Tanker decantation at a petrol pump: the MDG 2024 checklist

Match the invoice first

On arrival, check the invoice against the lorry: lorry number, seal or lock numbers, compartments with product and quantity, the time it left the supply point, the 15°C density, and the dip rod with its calibration certificate, plus anything else your oil company has advised MDG 1.1. For the journey time, see VTS and route deviation.

The 14 steps

The numbers match clause 1.2(i) to (xiv).

Note: Sales from the tank you are about to fill stop before decanting begins and stay stopped until the transfer is complete MDG 1.2(vii).

Settle the lorry and check the seals

1. Park and secure. Level ground, 10 minutes to settle, earthing and bonding, a DCP extinguisher nearby, no plastic or PVC hose MDG 1.2(i).
2. Seals. Match the seal or lock on the delivery manifold and manhole covers to the invoice MDG 1.2(ii).
3. Master valves. On lorries calibrated with full lines, release the levers before dipping MDG 1.2(iii).

Check quality and quantity

4. Density. At 15°C by ASTM Table 53B (current table), within ±3.0 kg/m³ of the invoice density MDG 1.2(iv). If outside, MDG gives no step: follow your oil company, or call the supply location MDG 1.2(ix). See the invoice density check.
5. Certificate. Ask the driver for the calibration certificate. It shows product level and proof level MDG 1.2(v).
6. Dip rod. Check the Weights & Measures marks at the foot and at the proof level, then compare the rod with a standard measuring tape MDG 1.2(vi).
7. Dips and water. Dip every compartment with the certified rod and test each for water with paste, a suitable one for ethanol blends MDG 1.2(vii). See water finding paste.
8. Compartment samples. Drain about 20 litres from each manifold, fill a clear glass container, and write each compartment's density and temperature in the register MDG 1.2(viii).
9. Doubt about quality? Ask the supply location or the area field officer MDG 1.2(ix).

Samples, shortages and decanting

10. Retention samples. Once density is within the limit, draw composite bottom samples before unloading: 2 × 1 litre petrol and/or 1 × 1 litre diesel, after removing at least 20 litres from each compartment. Seal and label them; the dealer or representative and the driver both sign the label MDG 1.2(x) MDG 2.3. See retention samples.
11. Short dip or water. Make up the shortage through the dispensing pump, record each compartment's dip and quantity on the back of every invoice copy, and have the dealer or representative and the driver sign. Then decant MDG 1.2(xi). See short dip and water.

After the lorry is empty

12. Empty it fully before the lorry leaves MDG 1.2(xii).
13. Stock entry in the stock register or on the stock display board MDG 1.2(xiii).
14. Density after decanting. Run at least 50 litres through the pump, take a nozzle sample, and record its 15°C density in the density register, Annexure 1 format MDG 1.2(xiv) MDG Annexure 1. See reference density and the register.

When something is wrong

• The driver will not sign the sample label. Do not decant. Call the supply location or the sales officer MDG 2.3.
• Unusual deviation in time or route. Tell the supply location (before accepting the lorry) or the sales officer, and decant only on further instructions MDG 2.3 MDG 1.5(vii).
• Doubt about quality. Call the supply location or the area field officer MDG 1.2(ix).

A lorry carrying unauthorised product that is found decanting at the outlet is a critical irregularity, with termination at the first instance MDG 5.1.7 MDG 8.2.