The Indian standard covers virgin Group I to Group III base oils and re-refined Group I base oils. A marketing label should never replace the latest laboratory report.
Start with the applicable standard
IS 18722 (Part 1):2024 defines requirements and test methods for mineral-origin base oils. It states that the re-refined base oils covered by the standard pertain to Group I.
Review the properties that matter
- Kinematic viscosity and viscosity index.
- Sulphur and saturates.
- Flash point, colour and visible impurities.
- Variation across more than one batch.
Be careful with Group II claims
The standard defines Group II using at least 90% saturates and no more than 0.03% sulphur. Ask for a report that proves both before accepting the label or price.
Five supplier questions
- Which grade is this and can I see the current COA?
- How do key results vary across batches?
- Where and how is the oil re-refined?
- What documentation accompanies the order?
- Can I validate a sample in my own blend?
Reference: BIS publication bulletin listing IS 18722 (Part 1):2024. Ask BIS for the current complete standard before making a conformity claim.