| A | B |
| corrosive | a substance that attacks a solid, wearing it away |
| toxic | a substance that is poisonous |
| *oxidizing / oxidising | a substance that may or may not burn itself, but will release oxygen, causing another substance to catch on fire or burn easily |
| harmful | a substance that causes a variety of damaging effects; avoid contact with the skin |
| irritant | a substance that triggers asthma symptoms |
| flammable | a substance that catches on fire easily |
| hazard symbol | a sign or symbol that warns against specific dangers |