Safety data sheet (SDS): what it is, how to read it, and how to get SDS management under control

The safety data sheet (SDS) is the starting point for almost everything you do with a hazardous substance: the risk assessment, the control measures and the instructions at the workstation. Yet in a lot of organisations it never gets past a folder of PDFs nobody opens. That's a waste, because the sheet holds exactly the information your assessment needs. Its formal name is safety data sheet; you'll also hear safety sheet, or the older term MSDS.

What is a safety data sheet?

In the EU the SDS is governed by REACH (Regulation EC 1907/2006, Article 31). When a supplier sells you a hazardous substance or mixture, they have to give you an SDS free of charge, in the official language of the country where it's sold, and update it as soon as new information on the hazards or their control appears. The layout is fixed in Annex II: every sheet carries the same sixteen sections, in the same order. That's genuinely useful, because it means you always know where to look, whoever the supplier is.

One thing that trips people up: the SDS is about the substance, not about your workplace. It describes properties and general advice. Whether exposure during your tasks is acceptable isn't in there. You make that call yourself, in the risk assessment.

The sixteen sections at a glance

The structure is always the same: 1) identification of the substance and supplier, 2) hazard identification, 3) composition and ingredients, 4) first-aid measures, 5) firefighting, 6) accidental release measures, 7) handling and storage, 8) exposure controls and personal protection, 9) physical and chemical properties, 10) stability and reactivity, 11) toxicological information, 12) ecological information, 13) disposal, 14) transport, 15) regulatory information and 16) other information.

You don't need to read every sheet cover to cover. A handful of sections does most of the work in your assessment.

Which sections matter most on the floor?

Section 2, the hazards. This holds the hazard classification, the H-statements, the signal word (Danger or Warning) and the pictograms. It's the basis of every risk assessment: no hazard identified, no defensible judgement.

Section 3, composition. For a mixture this lists the hazardous ingredients with their CAS and EC numbers and concentrations. You need those to check exposure limits and toxicology per component, and to see whether there's a CMR substance in the mix.

Section 8, exposure limits and PPE. This is the section people skip most and need most. It carries the occupational exposure limits you assess against, and the recommended protective equipment. Without the limit from Section 8 you can't complete a quantitative exposure assessment.

Section 9, physical properties. Physical state, vapour pressure and boiling point decide how readily a substance gets into the air. A volatile liquid behaves nothing like a paste or a granulate, and that difference feeds straight into the inhalation risk.

Sections 7 and 14, storage and transport. Section 7 gives the requirements for safe handling and storage, such as keeping incompatible substances apart. Section 14 holds the dangerous-goods classification: the UN number, transport hazard class and packing group.

From SDS to risk assessment

This is where it often goes wrong in practice. A full folder of SDSs feels like being sorted, but it isn't. The SDS is a building block. Occupational-safety law asks for a judgement about the risk at your workplace, and that judgement is yours to make. In the EU framework that means assessing the risk per substance, per task and per exposure route.

The principle is simple: risk is hazard × exposure. Section 2 gives the hazard. How you work with the substance — how much, how long, how volatile, open or closed handling — sets the exposure. Only when you combine the two do you have a defensible judgement and can pick the right control measures. Work down the hierarchy of controls: tackle the source first, then engineering and organisational measures, with PPE as the last line.

Why SDS management goes wrong in practice

In practice we see the same problems come back again and again.

Outdated versions. An SDS has no expiry date, but suppliers revise their sheets regularly. Check the revision date in Section 16. If you're still working from a sheet that's years old, the classification may no longer be right. Outdated sheets are the classic finding in an inspection.

Missing or wrong-language sheets. Every hazardous substance in use should have a current SDS in the required language in your file. A sheet that happened to come along in another language doesn't count.

Section 8 goes unused. Plenty of files collect the sheets neatly but never use the exposure limits to test exposure. Then the assessment has lost its yardstick.

No line from sheet to control. The SDS, the risk assessment and the workplace instruction card belong together. Left as separate documents in separate folders, you can't show how you got from hazard to control measure. And that's exactly what an inspector wants to see.

How to get your SDS management under control

1. Bring everything into one place. A single overview of the substances at your workplace, each with its current SDS. Scattered folders and stray PDFs make management almost impossible.

2. Keep an eye on the revision date. Set things up so you're alerted automatically when a sheet ages, instead of finding out by accident.

3. Pull the data out of every sheet. Capture the H-statements, ingredients, exposure limits and physical properties per substance, so you can use them in your assessment instead of searching each time.

4. Link sheet, assessment and workplace instruction card. Make the line from hazard to control traceable, so that on any question or inspection you can show straight away how you reached your judgement.

5. Keep it up. SDS management isn't a one-off job. New substances, new versions and changed classifications all need upkeep.

How Chemspark helps

Chemspark turns SDS management into an ongoing process instead of a folder that goes stale. You upload an SDS and Chemspark pulls out the hazards, ingredients, exposure limits and physical properties automatically. From those and your answers about use, it runs a qualitative risk assessment for inhalation, dermal and fire and explosion risk, with reasoning you can walk through. Where a quantitative assessment is needed, it computes one per component against the exposure limit from Section 8. The register, the workplace instruction cards and the labels follow from that, and expired sheets are flagged for you. Your file stays current and traceable, so you're not searching when an inspection comes.