How SDS HQ classifies mixtures, where the data comes from, and what we will and won't claim. Read this before trusting any output.
SDS HQ generates Safety Data Sheets compliant with the U.S. OSHA Hazard Communication Standard (29 CFR 1910.1200), updated by the May 2024 final rule that aligns the U.S. workplace standard with the seventh revised edition of GHS, with select Rev 8 provisions.
We do not currently produce SDSs valid in
A document generated here may be acceptable in non-U.S. workplaces that recognize HCS 2024 as substantially equivalent — but verifying that is the user's responsibility, not ours.
The engine applies the GHS Rev 9 Annex I rule set as adopted by HCS 2024, computing all 14 GHS hazard classes — ten health, three physical (flammable liquids, oxidizing liquids, corrosive to metals), and the aquatic environmental class — from composition, first-principles. Not by template-matching against a library of finished SDSs.
Every result includes an audit-trail calculation string: which substance contributed what, which cutoff or formula applied, and which Purple Book section governed the decision.
The six GHS bridging principles (§1.3.4) — dilution, batching, concentration, interpolation, substantially similar mixtures, and aerosols — are implemented and available during authoring: on the Classification step, an author can inherit a previously classified reference SDS's health and environmental hazards after the engine checks the principle's preconditions. The finished sheet discloses "Classification by bridging" and the principle applied in Section 2, and records the method per hazard in Section 11. Physical hazards are never inherited — they always reflect the product's own data.
These feed Section 15 of generated SDSs: the EPA TSCA inventory flag, SARA §313 and CERCLA reportable quantities, and the California Prop 65 list with listing dates — plus a library-wide watchlist covering ECHA SVHC and TSCA §6 restricted substances.
Regulatory updates are absorbed on a monthly cycle: OSHA Federal Register notices, OSHA Letters of Interpretation, EPA TSCA inventory updates, and California OEHHA Prop 65 list changes. Material changes are summarized in the change log with the engine version they shipped in.
SDS HQ provides a software tool for authoring Safety Data Sheets. The user — and their employer — is responsible for verifying the accuracy and completeness of any SDS produced for their specific use case, jurisdiction, and distribution scope. The tool is not a substitute for licensed regulatory expertise where the chemistry, end-use, or jurisdictional posture is materially complex. Use at your own risk.