Hazards and controls
Every student who walks into a teaching lab encounters the same hazards. How well they recognize and respond to them depends on what they learn before they arrive.
Reading the labels
The Globally Harmonized System assigns a pictogram to every major hazard class. Flammable, corrosive, toxic, oxidizing, and pressurized gases each have a distinct symbol you should be able to identify without reading the text.
In a teaching lab those symbols appear on reagent bottles, prep-room shelves, and storage cabinets. Before your first session, work through the nine GHS pictograms until they are automatic. Lab accidents rarely announce themselves slowly.
Safety Data Sheets and why you need them
A Safety Data Sheet for every reagent used in the department is available in the prep room and on the chemistry department portal. Section 2 lists hazard identification. Section 8 lists exposure controls and PPE. Section 13 covers disposal.
Faculty and TAs are responsible for knowing Sections 2, 8, and 13 before running any procedure. Students are expected to read the SDS for any reagent they handle independently. Ignorance is not a defense in a chemical exposure incident.
Matching PPE to the hazard
Nitrile gloves protect against most aqueous solutions and mild organics. They do not protect against chlorinated solvents, concentrated acids, or cryogenic materials. Knowing the limitation is as important as wearing the glove.
Eye protection is required from the moment you enter the lab, not just when you start a reaction. Splash goggles, not safety glasses, are required for any procedure involving open vessels of corrosive or volatile reagents. Lab coats cover skin. Closed-toe shoes are mandatory.










