Class 6 labels: toxic and infectious substances (white, skull or three crescents)
The package contains a toxic substance (6.1: pesticides, some chemicals) or an infectious substance, category A (6.2: cultures of dangerous pathogens).
Who puts it on the box
The sender (consignor): laboratories, hospitals, chemical suppliers.
How to read it
Do not open or handle a damaged package; report it. Most patient samples do not carry the 6.2 label: category B samples travel as UN 3373 with a diamond showing “UN3373” and the words “Biological substance, category B”.
What it does not promise
It does not promise the package is sealed or safe to touch if damaged, and the absence of the label does not promise a medical sample is harmless.
A mark on a parcel is the sender’s statement about what is inside and how it should be handled. It is not a certificate that the parcel is packed safely, that anyone handled it as marked, or that your carrier accepts it: for what you may send, read the carrier’s own terms.
- What it looks like
- 6.1 toxic: a skull and crossbones on white, figure 6. 6.2 infectious: three crescents on a circle (the biohazard sign) on white, figure 6, with the words “infectious substance” in some versions.
- Regulation
- ADR 2025, 5.2.2.2.2, label models No. 6.1 and 6.2; UN Model Regulations 5.2.2.2.2
- Kind of mark
- A dangerous-goods mark or label from the UN Model Regulations, applied in Europe by ADR (road) and its sister agreements for rail and waterways, and on the same pattern by the US 49 CFR. It says the package holds dangerous goods.
- Also called
- Toxic label; Poison label; Infectious substance label; Biohazard label
Related
Other marks with the same shape
Sources
Each document was fetched and read on the date shown. Written in our own words; quotations are the documents’ wording.
- Regulator guidance — Health and Safety Executive (UK regulator for the carriage of dangerous goods): Carriage of dangerous goods manual — Consignment procedures: marking and labelling of packages (ADR 5.2) — Package labels are the “hazard diamonds” of ADR 5.2.2 with the class number; specimen labels are in ADR 5.2.2.2.2 and sizes in 5.2.2.2.1.1; the consignor is responsible for marking and labelling. Checked 2026-09-27.
- Law adopting the same mark — US Government Publishing Office (govinfo), 49 CFR, edition of 1 October 2024: 49 CFR Part 172 Subpart E — Labeling (§§ 172.400–172.450, the hazard class labels) — §§ 172.429–172.432: the POISON label (skull, white) and the INFECTIOUS SUBSTANCE label on a white background. Labels are at least 100 mm on each side with an inner border about 5 mm inside the edge (§ 172.407). Checked 2026-09-27.