SDS Format Requirements: OSHA’s 16 Sections and 2024 Update

SDS format requirements come from OSHA’s Hazard Communication Standard at 29 CFR 1910.1200, which locks every Safety Data Sheet in the United States into a standardized 16-section structure that must appear in a fixed order.¹ Sections 1 through 11 and Section 16 carry mandatory content OSHA enforces. Sections 12 through 15 must appear on the sheet by heading but their content falls under other agencies’ jurisdiction.

The 16 Sections and What Each Must Contain

The section order is fixed. Preparers have some flexibility in how they arrange information within a section, but they cannot reorder, rename, or skip sections.

Section 1 — Identification

The product identifier as it appears on the label, other names or identifiers for the chemical, recommended uses and any restrictions on use, and the manufacturer’s or importer’s name, U.S. address, U.S. phone number, and emergency phone number.¹

Section 2 — Hazard Identification

The hazard classification, the signal word (“Danger” for more severe hazards, “Warning” for less severe), hazard statements, precautionary statements, and GHS pictograms. Any hazard that doesn’t fit a standard classification category must be described here. If a mixture contains 1% or more of an ingredient with unknown acute toxicity and the mixture has not been tested as a whole, the SDS must state the percentage of unknown-toxicity ingredients.¹

The eight standardized pictograms are red diamond-bordered symbols. A single chemical can carry more than one:

Flame: flammable materials, self-heating chemicals, and those that emit flammable gas
Flame Over Circle: oxidizers
Exploding Bomb: explosives, self-reactive chemicals, and organic peroxides
Gas Cylinder: gases under pressure
Corrosion: chemicals that cause skin burns, eye damage, or corrode metals
Skull and Crossbones: acutely toxic chemicals
Health Hazard: carcinogens, reproductive toxins, respiratory sensitizers, and chemicals causing organ damage
Exclamation Mark: irritants, skin sensitizers, and chemicals with narcotic effects²

Section 3 — Composition/Information on Ingredients

For pure substances: the chemical name, common names, CAS number, and any classified impurities or stabilizing additives. For mixtures: the chemical name, CAS number, and exact concentration (or concentration range) of every ingredient classified as a health hazard. Exact percentages are required unless a trade secret claim is made.¹

Section 4 — First-Aid Measures

Necessary response for each exposure route: inhalation, skin contact, eye contact, and ingestion. Also the most important symptoms, both immediate and delayed, and any special medical treatment needed.

Section 5 — Fire-Fighting Measures

Suitable and unsuitable extinguishing methods, hazardous combustion products the chemical can produce, and any special protective equipment firefighters should use.

Section 6 — Accidental Release Measures

Personal precautions, protective equipment, emergency procedures, and methods for containment and cleanup after a spill or leak.

Section 7 — Handling and Storage

Precautions for safe handling and conditions for safe storage, including chemical incompatibilities that could create dangerous reactions.

Section 8 — Exposure Controls/Personal Protection

The OSHA permissible exposure limit (PEL) and the ACGIH Threshold Limit Value (TLV) for each ingredient listed in Section 3, plus any other recommended exposure limits. Appropriate engineering controls and personal protective equipment also go here.

Section 9 — Physical and Chemical Properties

Measurable characteristics including appearance, odor, pH, melting point, boiling point, flash point, evaporation rate, flammability, vapor pressure, vapor density, relative density, solubility, partition coefficient, auto-ignition temperature, decomposition temperature, and viscosity.

Section 10 — Stability and Reactivity

Whether the chemical is stable under normal conditions, the possibility of hazardous reactions, conditions to avoid such as heat or static discharge, and incompatible materials.

Section 11 — Toxicological Information

Routes of exposure, related symptoms, and both acute and chronic health effects. Numerical toxicity measures and known or suspected carcinogenicity belong here.

Sections 12 Through 15

These four sections must appear on the sheet by heading, but their content is not enforced by OSHA:

Section 12 — Ecological Information: environmental toxicity, persistence, bioaccumulation potential, and mobility in soil
Section 13 — Disposal Considerations: proper disposal methods for the chemical and contaminated packaging
Section 14 — Transport Information: UN number, proper shipping name, transport hazard class, packing group, and special precautions
Section 15 — Regulatory Information: safety, health, and environmental regulations specific to the product not already covered elsewhere on the SDS

Section 16 — Other Information

The date the SDS was prepared or last revised, plus any other information the preparer considers useful.¹

Which Sections OSHA Actually Enforces

The enforcement split trips up a lot of preparers. OSHA requires the headings for Sections 12 through 15 to be present, but it does not enforce the content within them because that subject matter falls under the EPA (ecological information and disposal), the DOT (transport), and other agencies.³ Those agencies can still cite deficiencies in their own domains. DOT enforces shipping classifications, EPA enforces disposal, and international customers routinely expect all 16 sections to be complete. Leaving them empty is technically allowed under the HCS but rarely practical.

Sub-Heading Completeness, Language, and Legibility

Within every mandatory section, all specified sub-headings must be addressed. If no relevant data exists for a sub-heading, the SDS must clearly state that no applicable information is available. Leaving the space blank is not compliant.³

The chemical manufacturer or importer is responsible for ensuring the SDS is in English. Employers may keep copies in additional languages for multilingual workforces, but the English version is the baseline requirement. The document must be legible and presented in a consistent format. Where complex mixtures share similar hazards and essentially the same ingredients but vary in specific proportions, a single SDS can cover all of the related mixtures.

Trade Secret Handling in Section 3

A manufacturer or importer can withhold a chemical’s specific identity or exact concentration from Section 3, but only under strict conditions. The claim must be supportable as a genuine trade secret, the SDS must still disclose all information about the chemical’s properties and health effects, and the sheet must clearly state that the identity or concentration is being withheld.⁴

When exact concentration is claimed as a trade secret, the SDS must now provide the concentration as one of 13 prescribed ranges (for example, “1% to 5%” or “10% to 30%”), using the narrowest range that covers the actual concentration. This prescribed-range requirement was added in the 2024 HCS update and replaces the older practice of omitting concentration data entirely.⁵

Trade secret protection has a hard limit in medical emergencies. When a treating health care professional determines that knowing the chemical identity or concentration is necessary for emergency treatment, the manufacturer or importer must disclose it immediately, without waiting for a written request or confidentiality agreement. The paperwork can be handled after.⁴

The 2024 Update and Which Version Applies Now

In 2024, OSHA finalized a major revision aligning the HCS primarily with GHS Revision 7, while incorporating some non-animal testing methods from GHS Revision 8 for skin corrosion and irritation classifications.⁵ The update added a new physical hazard class for desensitized explosives, revised the flammable gases and aerosol categories, and introduced the prescribed concentration ranges for trade secret ingredients described above.

The compliance timeline matters if you are preparing or reviewing an SDS right now. The deadline for manufacturers, importers, and distributors to evaluate certain substances was extended to May 19, 2026, and all other compliance dates were pushed back by four months. During the transition, you can comply with the previous version of the standard, the updated version, or both.⁶

When the Sheet Has to Be Updated

An SDS is a living document. When the party preparing the SDS learns of significant new information about a chemical’s hazards or protective measures, the sheet must be updated within three months. If the chemical is not currently being produced or imported, the update must happen before the chemical re-enters the workplace.³ The SDS must accurately reflect the scientific evidence used in the hazard classification, so outdated content is a compliance failure, not a housekeeping issue.

1
Occupational Safety and Health Administration. 1910.1200 App D – Safety Data Sheets (Mandatory)
2
Occupational Safety and Health Administration. Hazard Communication Standard Pictogram
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eCFR. 29 CFR 1910.1200 – Hazard Communication
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eCFR. 29 CFR 1910.1200 – Hazard Communication
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Occupational Safety and Health Administration. Hazard Communication Standard (HCS) Alignment with the Globally Harmonized System (GHS)
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Occupational Safety and Health Administration. HCS 2024 Compliance Date Extension Notice