Multi-Supplier Fragrance Blends: Your CLP Compliance Guide
You've just created your best-selling candle yet — a signature blend of three fragrance oils, each from a different supplier. The scent is incredible. Your customers love it. But there's a compliance question nobody talks about: how do you produce a single, legally compliant CLP label when your candle contains fragrances from multiple sources?
The short answer: each oil's SDS contributes to the final classification. The long answer: this guide walks you through exactly how.
The Problem Nobody Talks About
Most CLP guides assume a simple scenario: one candle, one fragrance oil, one SDS. Reality is messier. UK candle makers frequently:
- Blend 2–3 fragrance oils to create a unique scent profile
- Source different oils from different UK or EU suppliers
- Adjust ratios seasonally or per batch
- Use a "base note" oil from one supplier and a "top note" from another
Each of these scenarios changes the CLP classification of your finished candle. You cannot simply pick the "strictest" label from one supplier and apply it. The law requires a specific calculation.
The Additive Method: How It Works
CLP Regulation (EC) No 1272/2008 prescribes the additive method (also called the summation method) for classifying mixtures when you have ingredient data. Here's the step-by-step process:
Step 1: Gather Every SDS
You need the Safety Data Sheet for each fragrance oil in your blend. Specifically, Section 3 — which lists every chemical component and its concentration range.
️ If a supplier refuses to provide an SDS, that's a red flag. Under REACH and CLP law, they are legally required to supply one for hazardous mixtures.
Step 2: Calculate Actual Concentrations in Your Candle
Each SDS component concentration must be multiplied by two factors:
- The oil's proportion in your blend (e.g., Oil A is 60% of your fragrance mix)
- The total fragrance load in your candle (e.g., 8% of the total wax weight)
Formula: Final concentration = SDS component % × Oil blend ratio × Fragrance load %
Step 3: Apply Cut-off Values
Compare each resulting concentration against CLP classification thresholds. For example:
| Hazard Category | Threshold for Cat 1 | Threshold for Cat 1A |
|---|---|---|
| Skin Sensitisation | ≥ 1% | ≥ 0.1% (triggers EUH208) |
| Aquatic Toxicity (Acute) | ≥ 1% | — |
| Aquatic Toxicity (Chronic) | ≥ 1% | ≥ 0.1% |
| STOT Single Exposure | ≥ 1% | ≥ 0.1% |
Step 4: Sum Across All Oils
Here's the critical step that makes multi-supplier blends tricky: if the same hazardous component appears in multiple oils, you must sum their concentrations before comparing against thresholds.
For example, if Oil A contains Linalool at 15% and Oil B contains Linalool at 8%, and both oils are used at 50% of the blend with a 10% fragrance load:
- From Oil A: 15% × 0.5 × 0.10 = 0.75% Linalool in final candle
- From Oil B: 8% × 0.5 × 0.10 = 0.40% Linalool in final candle
- Total Linalool: 1.15% → exceeds 1% threshold → Skin Sensitisation Cat 1
Neither oil alone would have triggered the classification. Only the combined calculation reveals the true hazard.
What This Means for Your Label
Based on the calculation above, your candle's CLP label must include:
- Pictogram: GHS07 (Exclamation mark)
- Signal word: "Warning"
- H-statement: H317 — "May cause an allergic skin reaction"
- EUH208: "Contains Linalool. May produce an allergic reaction."
- P-statements: P261, P280, P302+P352, P333+P313, P321, P501
Common Multi-Supplier Mistakes
❌ Mistake 1: "I'll just use the worst-case label"
Using the strictest label from any single oil is legally insufficient. The additive method can create classifications that no single oil triggers. You'll miss hazards — and that's a compliance breach.
Mistake 2: "I'll ask one supplier to do it"
Suppliers only have data for their own oil. They cannot classify a blend they've never seen. Their SDS covers their product, not your finished candle.
❌ Mistake 3: "I'll update the label when I change the recipe"
Every time you change oil ratios or swap a supplier, the classification may change. Each formulation needs its own CLP assessment. A label created for a 50/50 blend is invalid for a 70/30 blend.
❌ Mistake 4: Ignoring the "worst-case concentration" rule
When an SDS gives a concentration range (e.g., "5–10%"), CLP requires you to use the upper bound for classification. Always calculate using the worst-case value.
How PixHarvest Handles Multi-Supplier Blends
When you send us your formula, we:
- Request or verify the SDS for every oil in your blend
- Extract all Section 3 components with their upper-bound concentrations
- Apply your exact blend ratios and fragrance load
- Sum shared components across all oils
- Run the full additive method against current GB and EU CLP cut-off values
- Produce a print-ready label with all required elements
- Include a classification record showing the full calculation trail
One label. One calculation. Full compliance — whether you use one oil or five.
Blending from multiple suppliers?
Send us your formula with each oil's SDS and we'll check the combined classification on your current label free, flagging any cross-supplier gaps — no obligation. A corrected compliant label is £39 per fragrance in 48 hours.
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