Reading a Safety Data Sheet

Every hazardous chemical on this site has a safety data sheet, and you have a right to see it. They all follow the same 16 sections in the same order, which means once you know where to look, any SDS reads the same.

The four sections that matter at the point of use

• Section 2 — Hazard identification. What it does to you. Pictograms, signal word, hazard statements. Read this before anything else.
• Section 4 — First aid. What to do in the first minute. Read it *before* you need it, because you will not be reading anything afterwards.
• Section 7 — Handling and storage. What not to store it next to.
• Section 8 — Exposure controls and PPE. Which gloves, which respirator, what ventilation. "Gloves" is not an answer — nitrile, neoprene and latex behave completely differently against different chemicals.

Section 9 gives flash point. Section 10 tells you what it reacts with.

The label

Every container gets a label. If you decant something into a secondary container and it does not stay in your hand until it is empty, that container gets labelled too.

The signal word tells you the severity: Danger is the more severe, Warning the less. There is no third word.

The pictograms

Eight red diamonds, and three get confused:

• Flame — flammable
• Exclamation mark — irritant, less serious health effect
• Health hazard (a person with a starburst on the chest) — the serious one: carcinogen, respiratory sensitiser, reproductive toxicity
• Corrosion — burns skin, eats metal
• Skull and crossbones — acutely toxic

Exclamation mark and health hazard look similarly mild on a label and are not remotely the same thing.

In practice

Know where the SDSs are kept and how to get one at 3am. Never use an unlabelled container. And if a chemical is new to this site, read Section 2 before you open it, not after you spill it.