- Both countries let suppliers withhold an ingredient's exact concentration as a trade secret, if section 3 gives one of 13 prescribed ranges instead.
- The 13 ranges are the same in Canada (HPR sections 4.4.1 and 4.5) and the US (29 CFR 1910.1200(i)(1)(iv)).
- A narrower range that sits entirely inside a prescribed range is allowed in both countries. The SDS must say the concentration is withheld as a trade secret.
- Withholding a chemical name is a different process: in Canada it needs a claim filed with Health Canada; in the US the claim must be supportable but is not filed.
Section 3 of an SDS lists the ingredients and their concentrations. Formulators often consider exact percentages confidential, and both Canada and the US allow them to be withheld. Since OSHA's 2024 update, the two countries do it the same way: by giving a prescribed concentration range instead of the exact figure.
The 13 prescribed ranges
| Range | Range | Range |
|---|---|---|
| 0.1% to 1% | 7% to 13% | 60% to 80% |
| 0.5% to 1.5% | 10% to 30% | 65% to 85% |
| 1% to 5% | 15% to 40% | 80% to 100% |
| 3% to 7% | 30% to 60% | |
| 5% to 10% | 45% to 70% |
The ranges overlap on purpose, so most concentrations fit more than one. In the US, the range used must be the narrowest possible.
The rules in Canada
For an ingredient whose concentration does not vary, section 4.4.1 of the Hazardous Products Regulations allows the SDS to give the actual concentration, a prescribed range that contains it, or a narrower range that falls entirely within a prescribed range. Section 4.5 covers concentrations that vary between batches: the SDS can give the actual range, a prescribed range that contains it, a narrower range within a prescribed range, or, for actual ranges between 0.1% and 30% that do not fit a single prescribed range, two consecutive prescribed ranges combined. When a range is given instead of the actual value, the SDS must include a statement that the actual concentration (or concentration range) is withheld as a trade secret.
The rules in the US
Under paragraph (i)(1) of the Hazard Communication Standard, a manufacturer, importer or employer may withhold the exact concentration if the trade secret claim can be supported, the SDS still discloses the properties and effects of the chemical, the SDS says the concentration is being withheld as a trade secret, and the concentration is given as one of the prescribed ranges. The range must be the narrowest possible. Two consecutive ranges between 0.1% and 30% may be combined when no single range fits, and a narrower range than those prescribed is allowed.
Withholding a chemical name is different
- Canada: to withhold the chemical name or other identity information, the supplier files a claim for exemption under the Hazardous Materials Information Review Act. The SDS must then show that a claim was filed, the filing date and the registry number, and later that an exemption was granted.
- US: the specific chemical identity may be withheld if the claim can be supported and the SDS says it is withheld. Nothing is filed with OSHA, but the identity must be disclosed to health professionals in the situations the standard sets out, such as a medical emergency.
Common mistakes
- A range that is not on the list, such as "10 to 20%" or "<5%", with no indication that it falls inside a prescribed range.
- A wider range than necessary on a US SDS.
- No statement that the concentration is withheld as a trade secret.
- Different ranges for the same ingredient on the Canadian and US versions of the SDS.
- A withheld chemical name on a Canadian SDS with no claim filed.
Older Canadian SDSs may predate the 2022 amendments to these sections, which also changed which ingredients must be listed. See the WHMIS transition is over.
Sources
General information, not legal advice. Checked against the official sources above on 10 October 2026. Rules change: for your own products, ask for a spot-check.
