Safety Data Sheets (SDS): The 16-Section Format

A safety data sheet (SDS) is a standardized 16-section document that communicates the hazards, safe handling, and emergency response information for a hazardous chemical. Under OSHA's Hazard Communication Standard, 29 CFR 1910.1200(g), employers must keep an SDS for every hazardous chemical readily accessible to workers on every shift.

If you started in a plant before 2012, you called these MSDS, and every manufacturer wrote them in a different order. The move to GHS fixed that: same 16 sections, same order, on every sheet for every chemical, so the person who needs the fire-fighting information can find it in the same place whether the drum came from one supplier or another. This post walks the 16 sections, shows which ones OSHA actually enforces, spells out the employer's duties, and covers how to keep an SDS library usable on the floor. It is educational, not legal advice.

What is a safety data sheet, and what changed with GHS?

An SDS is the detailed hazard reference behind the label on a chemical container. The label gives you the quick warning, the pictogram, the signal word, the hazard statements; the SDS gives you the full story: what is in it, what it does to you, how to handle it, what to do when it spills or catches fire. When OSHA aligned the Hazard Communication Standard with the Globally Harmonized System, the old material safety data sheet (MSDS) became the safety data sheet (SDS), and the free-form layout became a mandatory 16-section format so information always lands in a predictable place.

That predictability is the practical win. Before GHS, a maintenance tech dealing with a splash had to hunt through a differently organized sheet for every chemical to find the first-aid steps. Now first aid is always section 4, spill response is always section 6, and the PPE requirement is always section 8, whether the container came from a national supplier or a small specialty vendor. The standard did not just add sections; it made the sheet fast to use under pressure, which is the only time it truly matters.

Which sections does OSHA actually enforce?

Sections 1 through 11 and section 16, plus every section must still appear. OSHA enforces the content of the first eleven sections and the last one, which cover the information workers need to protect themselves. Sections 12 through 15, ecological information, disposal, transport, and other regulatory details, fall under the jurisdiction of other agencies, so OSHA does not enforce their content. They still have to be on the sheet, in order; OSHA simply will not cite a manufacturer over what section 13 says.

What are the employer's duties under 1910.1200(g)?

Have one, keep it current, and make it reachable at the point of use. Paragraph (g) of the standard puts a short list of duties on the employer. Maintain a copy of the SDS for each hazardous chemical in the workplace. Keep those sheets readily accessible to employees in their work area during each work shift, no locked office, no "ask the manager for the key." Make sure new and updated sheets arrive and get filed when chemicals or formulations change. And back it with training, so workers know the sheets exist, where they live, and how to read them. Manufacturers and importers carry the upstream duty to develop the SDS and ship it; the employer's duty is to hold it where the work happens.

"Readily accessible" is where plants get tripped up. A binder in a manager's office that is locked on nights and weekends is not readily accessible to the crew running the chemical at 2 a.m. Neither is a computer system nobody can reach when the network is down. The test is simple: can the person handling the drum, on their shift, get to the sheet fast enough to matter in a spill or an exposure?

How does an SDS reach the person handling the chemical?

Down a chain, and every link has a duty. The chemical manufacturer or importer classifies the product's hazards and develops the SDS. The distributor passes that sheet along, at or before the first shipment, and again whenever it changes. The employer receives it, files it into the plant's library, and makes it reachable at the point of use. The worker, trained on where the library lives and how to read a sheet, pulls it when they need it. A break anywhere in the chain, a sheet that never shipped, a sheet that never got filed, a library nobody can reach, leaves the person at the end of it exposed with no reference.

How do you manage an SDS library on the floor?

Treat it like inventory, because it is: one entry per hazardous chemical, kept current, indexed so people can find a sheet fast.

1. Inventory the chemicals actually present in the plant, by area. You cannot maintain sheets for a list you do not have, and the list drifts every time purchasing tries a new cleaner.
2. Match a current SDS to each one and flag the gaps. Every hazardous chemical on the floor needs a sheet; a chemical with no sheet is the finding an auditor writes up first.
3. Index it for retrieval. Alphabetical by product name is fine on paper; searchable by product, area, or hazard is better. The measure is how fast someone finds the right sheet, not how neat the binder looks.
4. Put access at the point of use. The crew running a chemical should reach its sheet from their work area on their shift, not walk to an office that may be locked.
5. Cover backups. If the library is electronic, have a plan for when the network or power is down, because that is exactly when a spill happens.
6. Update on change. New chemical, new supplier, reformulated product, or a revised sheet from the manufacturer, each triggers a library update.
7. Retire what's gone, but keep records: employers generally must retain exposure-related records for decades, so archive superseded sheets rather than shredding them.
8. Audit the library as part of the regular safety audit: pick five chemicals off the floor and see how fast the current sheet turns up.

How do you read an SDS when something goes wrong?

Know which section answers which emergency before the emergency. In the moment, nobody reads sixteen sections front to back. The fixed order is the whole point, because it lets you jump:

• Someone is exposed: section 4, first-aid measures, by route (eye, skin, inhalation, ingestion).
• It's on fire: section 5, fire-fighting measures, including which extinguishing media to use and which to avoid.
• It spilled: section 6, accidental release measures, for containment and cleanup.
• Before the job: sections 7 and 8, handling, storage, exposure limits, and the PPE the task requires, which feed straight into the chemical's job safety analysis.

Sections 7 and 8 are also where SDS work connects to the rest of the safety program. The PPE and engineering controls listed there belong in the task's JSA, incompatibilities in section 7 drive how chemicals get stored and separated, and servicing equipment that holds hazardous chemical usually means an energy-and-material isolation step, the same discipline as lockout/tagout. The SDS is a reference; the safety program is where its contents get used.

What do the standards say?

Straight from the primary sources:

• The requirement lives in OSHA's Hazard Communication Standard, 29 CFR 1910.1200; paragraph (g) covers safety data sheets.
• The mandatory 16-section content and order are set out in Appendix D to 1910.1200.
• OSHA's Hazard Communication resources note that HazCom is consistently among the most frequently cited standards in general industry, and missing or inaccessible SDSs are a common citation.

The recurring failure is not the sheets; it is access. The library is a binder in an office, or a system nobody can reach from the floor, so the sheet that should surface in thirty seconds during a spill takes ten minutes and a phone call. Harmony connects machines, software, and paperwork into one operational layer with no rip-and-replace: the SDS library becomes searchable from the tablet already at the station, indexed by product, area, and hazard, so a worker pulls the right sheet, and jumps to section 4 or 6, at the moment it matters. AI search returns cited answers across SDSs, SOPs, and the safety committee's open actions, part of the everyday shape of connected worker technology (see how it works). Harmony is not a chemical-safety product, but it keeps the sheet where the work is.