Contents
In short: Section 3 of a safety data sheet says what the product is made of, but only as far as the law requires. For a substance it names the main constituent and any classified impurities or additives. For a mixture it lists the ingredients that are classified above set concentration thresholds, plus those with a workplace exposure limit or PBT/vPvB properties, each with an identifier, a concentration or range and a classification. The EU and the US use different thresholds, which is why a sheet written for one market often needs rework for the other.
Substances: Section 3.1
For a substance, REACH Annex II (as amended by Regulation (EU) 2020/878) asks for the main constituent, identified at least by the product identifier or another identification means from subsection 1.1. Any impurity, stabilising additive or other constituent that is itself classified and contributes to the classification of the substance must also be identified, by its CLP product identifier or, if none exists, by another name or an identification number. Listing all constituents, including non-classified ones, is optional. Subsection 3.1 may also be used to describe multi-constituent substances.
In the US, Appendix D to 29 CFR 1910.1200 asks for the chemical name, common name and synonyms, the CAS number and other unique identifiers, and impurities and stabilising additives that are themselves classified and contribute to the substance's classification.
Mixtures: which ingredients must be listed
For a mixture, Annex II requires the product identifier, the concentration or concentration range and the classification of at least every substance covered by subsections 3.2.1 or 3.2.2. The hazards of the mixture as a whole belong in Section 2, not here. The thresholds depend on whether the mixture itself meets the classification criteria.
Mixture that meets the classification criteria (3.2.1)
- Substances classified for a health or environmental hazard, present at or above the lowest of the applicable limits: the generic cut-off values in Table 1.1 of CLP Annex I, the generic concentration limits in its parts 3 to 5, specific concentration limits, the cut-off adjusted by an M-factor, or the limits in CLP Annex II.
- Substances with a workplace exposure limit not already covered by the point above.
- PBT and vPvB substances (Annex XIII criteria) and substances on the Article 59(1) candidate list for reasons other than the hazard classes above, when the individual substance is at 0.1 % or more.
Some of the generic cut-off values in Table 1.1 are shown below.
| Hazard class and category | Cut-off for listing in Section 3 |
|---|---|
| Acute toxicity, categories 1 to 3 | 0.1 % |
| Acute toxicity, category 4 | 1 % |
| Skin corrosion/irritation, eye damage/irritation | 1 % |
| Respiratory or skin sensitisation | 0.1 % |
| Carcinogenicity (1A, 1B, 2), germ cell mutagenicity (1A, 1B), reproductive toxicity | 0.1 % |
| Germ cell mutagenicity, category 2 | 1 % |
| STOT single or repeated exposure, categories 1 and 2 | 1 % |
| Aspiration hazard | 10 % |
| Aquatic acute 1 and chronic 1 | 0.1 % |
| Aquatic chronic 2, 3 and 4 | 1 % |
A substance with an M-factor, or with a specific concentration limit below the generic value, must be listed at a lower concentration than the table shows. This is why the table is a starting point and not a substitute for the harmonised entry in CLP Annex VI. The classification itself is explained in CLP mixture classification.
Mixture that does not meet the criteria (3.2.2)
Substances are listed when present at 1 % by weight (non-gaseous mixtures) or 0.2 % by volume (gaseous mixtures) if they present a health or environmental hazard under CLP or have a workplace exposure limit, and at 0.1 % by weight if they are PBT or vPvB or are on the Article 59(1) list for other reasons.
What to show for each listed substance
- Name and numbers: the name and, if available, the REACH registration number. The EC number must be given if available; the CAS number and the IUPAC name may be given. A mixture supplier may omit the part of a joint-submission registration number that identifies the individual registrant, but must supply the full number to an enforcement authority within seven days of a request, or forward the request to its own supplier within the same period.
- Classification: hazard class(es) and category code(s) as in CLP Annex VI Table 1.1, and the hazard statements, which may be given as codes if Section 16 holds the full text.
- Reason for listing: if the substance is not classified, say why it appears, for example "substance with a workplace exposure limit" or "non-classified vPvB substance".
- Concentration: exact percentages or ranges, in descending order by mass or volume where technically possible.
Where a range is used, the health and environmental statements for the mixture must reflect the effect of the highest concentration in that range. A range of "1 to 50 %" therefore behaves like 50 % for hazard assessment, which is why very wide ranges undermine the sheet.
Trade secrets: CLP Article 24 and OSHA
EU. A manufacturer, importer or downstream user may ask ECHA for an alternative chemical name for a substance in a mixture, if the substance meets the criteria in CLP Annex I and disclosing the identity would put confidential business information, in particular intellectual property, at risk. If ECHA raises no objection within six weeks of the request or of the further information it asked for, the name is deemed to be allowed. For such a substance, the registration number, EC number and other precise identifiers need not be given in Section 3. If the classification later no longer meets the Annex I condition, the product identifier must be used again.
US. Appendix D defers to paragraph (i) of 29 CFR 1910.1200. The SDS must state that the specific chemical identity or the exact concentration has been withheld as a trade secret. Where the concentration is withheld, one of the prescribed ranges must be used: 0.1 to 1 %, 0.5 to 1.5 %, 1 to 5 %, 3 to 7 %, 5 to 10 %, 7 to 13 %, 10 to 30 %, 15 to 40 %, 30 to 60 %, 45 to 70 %, 60 to 80 %, 65 to 85 % or 80 to 100 %.
EU and US compared
| Point | EU (REACH Annex II) | US (HazCom Appendix D) |
|---|---|---|
| Which ingredients | Classified ones above cut-offs, plus workplace exposure limit and PBT/vPvB substances | Every ingredient classified as a health hazard, above its cut-off or presenting a risk below it |
| Identifier | Name, EC number if available, registration number if available; CAS optional | Chemical name and CAS number or other unique identifier; source of the identifier if no CAS |
| Concentration | Exact value or range | Exact percentage by default; ranges for trade secrets, batch variation or similar mixtures |
| Trade secret | Alternative chemical name approved via ECHA | Withholding statement; prescribed ranges if concentration is withheld |
The two systems share the same Section 3 position in the sheet. A sheet for several markets needs the identifiers and thresholds of each; see SDS requirements in the EU, UK and US compared. For the other fifteen sections, see the 16 sections explained.
Common mistakes
- A hazard in Section 2 that cannot be traced to any ingredient in Section 3.
- Using only the generic cut-off and ignoring M-factors or lower specific concentration limits.
- Omitting ingredients with a workplace exposure limit or PBT/vPvB properties because they are not classified.
- Ranges so wide that the classification cannot be verified.
- Listed percentages that do not add up, or an unclear basis (w/w or v/v).
- Wrong or missing CAS/EC numbers, or an EC number copied from a different substance.
- H statements in Section 3 that differ from those in Section 2 or Section 16.
- An alternative chemical name used without an ECHA decision, or a US trade secret claim with no withholding statement.
Frequently asked questions
Must every ingredient be listed?
No. Annex II requires the substances covered by the thresholds above. Suppliers may list all ingredients, including non-classified ones, but are not obliged to.
Can I use a concentration range in the EU?
Yes. Annex II allows exact percentages or ranges, where technically possible in descending order. The hazard statements must then reflect the highest concentration in the range.
Is the CAS number mandatory?
Under REACH Annex II the EC number must be given if available and the CAS number may be given. Under OSHA Appendix D the CAS number or another unique identifier is required.
This guide is general information; it is not legal advice and does not replace review by a competent person.
Sources
- REACH Annex II as amended by Commission Regulation (EU) 2020/878 — CELEX:32020R0878.
- UK REACH Annex II (GB text, structure parallel to the EU text) — legislation.gov.uk.
- CLP, Regulation (EC) No 1272/2008, Annex I and Article 24 — CELEX:02008R1272.
- 29 CFR 1910.1200, paragraph (i) and Appendix D — ecfr.gov; OSHA Appendix D.
Related codes
H and P statements related to this topic; each is explained in the glossary with its full wording, thresholds and label use.
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