Two exclamation marks in two bordered shapes, used in two different systems. Which one you are looking at tells you how precise the warning is.
Shape and setting decide it. A yellow triangle on a wall or a machine is the general safety warning sign: a hazard is present, unspecified, so read the text beneath it. A red-bordered diamond on a product label is the GHS pictogram, which is not vague at all — it stands for a defined set of chemical hazard classes such as skin or eye irritation.
Both put an exclamation mark inside a bordered shape; the GHS pictogram is a red-bordered diamond on packaging, this is a yellow triangle on signage.
Drawn from the visual attributes recorded for each symbol. Only traits the two records disagree about are listed.
| Trait | General warning symbol | GHS exclamation mark pictogram |
|---|---|---|
| Built from | triangles, lines and dots | letter like |
| Colour | yellow and black | black, red and white |
| General warning symbol | GHS exclamation mark pictogram | |
|---|---|---|
| Shape and colour | Yellow triangle, black border | White diamond, red border |
| Where you see it | Signage — walls, doors, machinery | Chemical product labels and packaging |
| How specific is it? | Deliberately unspecified; needs accompanying text | Precise — a defined set of hazard classes |
| What to do | Read the wording under the triangle | Read the hazard statements on the label |
| Relationship (from Symbolwise's records) | Commonly confused with GHS exclamation mark pictogram — Both put an exclamation mark inside a bordered shape; the GHS pictogram is a red-bordered diamond on packaging, this is a yellow triangle on signage. | Commonly confused with General warning symbol — Both enclose an exclamation mark in a bordered shape. This is a red-bordered diamond on chemical packaging with a defined set of hazard classes; the general warning sign is a yellow triangle on signage meaning unspecified caution. |
Wikipedia · retrieved 2026-07-31
Tertiary reference. Used for what the symbol depicts, its shape-and-colour category, and any ISO reference number it reports. The standards themselves are paywalled and were not consulted, so nothing here is treated as an official definition.
UNECE (United Nations Economic Commission for Europe) · retrieved 2026-07-27
Globally Harmonized System of Classification and Labelling of Chemicals
Wikipedia · retrieved 2026-07-27
The becquerel counts nuclear decays — one per second — and says nothing about harm. The sievert weights absorbed energy by the kind of radiation delivering it, and so estimates biological effect. A becquerel of one isotope and a becquerel of another can carry very different risk, which is exactly why exposure limits and medical doses are stated in sieverts and never in becquerels.
They are alternatives, not a pair. The double square means the appliance is protected by double or reinforced insulation and needs no earth connection, which is why it can legitimately have a two-pin plug. The earth symbol marks a terminal that must be connected, because that appliance relies on earthing instead.
A red ring with a diagonal bar forbids the thing shown. A solid blue disc requires it. So the same pictogram of a person means 'do not enter' in red and 'this way only' in blue. If the circle is filled it is an instruction; if it is an outline with a bar through it, it is a prohibition.