A Material Safety Data Sheet (MSDS) is a detailed document that provides information about the hazards, safe handling, storage, and emergency procedures for a chemical product used in the workplace. If you’ve come across this term recently, there’s an important update: the MSDS has been replaced by a standardized format now called simply a Safety Data Sheet (SDS). The content is similar, but the new version follows an internationally agreed-upon structure that makes chemical safety information consistent no matter where in the world you work.
From MSDS to SDS: What Changed
For decades, the MSDS was the standard way chemical manufacturers communicated hazard information to workers and employers. The problem was that every manufacturer could organize the information differently. One company’s MSDS might put fire hazard data on page two while another buried it on page six. In an emergency, that inconsistency cost time.
In 2012, OSHA updated its Hazard Communication Standard to align with the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals (GHS). This overhaul replaced the freeform MSDS with a standardized 16-section Safety Data Sheet. The goal was a common, coherent approach to classifying chemicals and communicating hazard information across countries and industries. OSHA issued another update in May 2024, aligning with the seventh revision of the GHS to further improve label and safety data sheet quality and better match standards used by Canada and other federal agencies.
If your workplace still refers to these documents as “MSDS,” the information is functionally the same, but the current legally required format is the SDS.
What an SDS Contains: The 16 Sections
Every Safety Data Sheet follows the same structure. Some sections matter more to you as a worker, others are primarily for emergency responders or safety professionals, but all 16 are required.
- Section 1: Identification. The product name, manufacturer’s contact information, recommended uses, and emergency phone number.
- Section 2: Hazard Identification. The most immediately useful section. It lists the chemical’s hazard classification (such as “flammable liquid, category 1”), a signal word (“Danger” or “Warning”), pictograms like a flame or skull-and-crossbones symbol, and precautionary statements telling you how to avoid harm. If the chemical is a mixture containing ingredients with unknown toxicity, this section states what percentage of the mixture those ingredients represent.
- Section 3: Composition/Information on Ingredients. Chemical names, common names, and concentrations of each hazardous ingredient.
- Section 4: First-Aid Measures. What to do if someone is exposed through the eyes, skin, breathing, or swallowing. It also describes important symptoms to watch for, both immediate and delayed.
- Section 5: Fire-Fighting Measures. Suitable extinguishing methods and any special hazards the chemical creates during a fire.
- Section 6: Accidental Release Measures. How to clean up a spill or leak safely.
- Section 7: Handling and Storage. Precautions for safe use, conditions for safe storage, and incompatibilities with other chemicals.
- Section 8: Exposure Controls/Personal Protection. Lists occupational exposure limits, including OSHA’s permissible exposure limits and recommended threshold limit values. This section also specifies what personal protective equipment you should wear, such as gloves, respirators, or eye protection.
- Section 9: Physical and Chemical Properties. Measurable characteristics like appearance, odor, pH, flash point (the temperature at which it can ignite), boiling point, vapor pressure, and flammability. If data isn’t available for a property, the sheet must note that explicitly rather than leaving it blank.
- Section 10: Stability and Reactivity. Whether the chemical is stable under normal conditions and what conditions or materials could cause a dangerous reaction.
- Section 11: Toxicological Information. Health effects from short-term and long-term exposure, including routes of exposure and symptoms.
- Section 12: Ecological Information. Effects on the environment if released.
- Section 13: Disposal Considerations. Guidance on safe disposal methods.
- Section 14: Transport Information. Shipping classifications and special precautions for moving the chemical.
- Section 15: Regulatory Information. Applicable safety, health, and environmental regulations.
- Section 16: Other Information. Any additional relevant details, including the date the SDS was prepared or last revised.
The Sections That Matter Most to Workers
If you’re trying to quickly understand a chemical you work with, focus on sections 2, 4, 7, and 8. Section 2 tells you what’s dangerous about it. Section 4 tells you what to do if something goes wrong. Section 7 tells you how to handle and store it without creating a hazard. Section 8 tells you what protective gear to use and how much exposure is too much.
Section 9 becomes important if you’re working with flammable materials. The flash point tells you the lowest temperature at which a chemical’s vapors can ignite. A flash point below room temperature means vapors could ignite at any moment in a normal workspace. Auto-ignition temperature, vapor density (whether fumes rise or settle to the floor), and evaporation rate all shape how carefully you need to ventilate your work area.
Your Right to Access These Documents
Under OSHA’s Hazard Communication Standard (29 CFR 1910.1200), employers must have a safety data sheet in the workplace for every hazardous chemical employees use. These sheets must be readily accessible during each work shift while you’re in your work area. Your employer can keep them as paper copies, store them electronically, or even integrate them into operating procedures, as long as nothing creates a barrier to immediate access.
If you request a copy, your employer must provide one at no cost to you, give you access to a photocopier at no cost, or lend you the document long enough to make your own copy. If there’s a delay, the employer has 15 working days to explain why and tell you the earliest date the record will be available.
Employers with multiple companies working on the same site, such as a construction project, must also ensure that contractors and their employees can access the SDS for every chemical they might be exposed to. The written hazard communication program at each workplace must include a list of all hazardous chemicals present, referenced by the same product identifiers used on the corresponding safety data sheets.
How SDS Documents Stay Current
Chemical manufacturers and importers are responsible for creating and updating safety data sheets. When new hazard information emerges, such as a newly discovered health effect or a change in toxicity classification, the manufacturer must revise the SDS and communicate that updated information. The date on section 16 lets you check how recent the document is. If you’re working with an SDS that’s several years old, it’s worth confirming with your employer or the manufacturer that no updates have been issued.
Employers don’t write the SDS themselves, but they are responsible for making sure the most current version is available. If a chemical’s formulation changes or new safety data becomes available, the updated sheet should replace the old one in your workplace’s files.
Why the Standardized Format Matters
The shift from the old MSDS to the standardized SDS wasn’t just bureaucratic housekeeping. In workplaces where dozens or hundreds of chemicals are present, a consistent format means workers can find critical information in seconds. Section 4 is always first aid. Section 8 is always protective equipment. That predictability matters when someone has just splashed an unknown liquid on their skin and needs an answer immediately.
The standardized format also means that a safety data sheet for a chemical made in Germany follows the same structure as one made in the United States or Japan. For companies that source materials internationally, this eliminates the confusion of navigating unfamiliar formats and reduces the chance that a critical hazard warning gets overlooked because it was organized differently than expected.