H311+H331: Toxic in contact with skin or if inhaled.

Hazard class and category

Hazard class	Category	Pictogram	Signal word	UN transport class
Acute toxicity, dermal; acute toxicity, inhalation	Category 3		Danger	—

This combined statement merges H311 and H331.

What H311+H331 means

Acute toxicity covers harmful effects that occur after a single exposure, or several exposures within 24 hours, by swallowing (oral), skin contact (dermal) or breathing in (inhalation). The GHS has five categories, from Category 1 (most toxic) to Category 5, based on lethal-dose or lethal-concentration data.

The product can cause serious harm, and in the worst categories death, after one short exposure. Categories 1 to 3 carry the skull-and-crossbones pictogram, and Category 4 carries the exclamation mark.

What to do

Avoid all contact, breathing and swallowing. Use only with good ventilation or local exhaust, wear the gloves, protective clothing and respiratory protection the SDS calls for, do not eat, drink or smoke while working, wash thoroughly afterwards, and call a poison center or doctor if exposed.

This is general guidance for the hazard class. The safety data sheet for your product always takes precedence.

Chemicals carrying H311+H331

Chemicals listed here carry H311 or H331 (or the combined code itself) in their primary classification.

17 chemicals in our database. Classification comes from each chemical's primary GHS source, so a supplier's SDS may differ.

H311+H331 frequently asked questions