The term "risk" is often confused with "hazard". A high voltage power supply, a sample of radioactive material, or a toxic chemical may present a hazard, meaning that they present the potential for harm. Concentrated acids, for example, pose a clear hazard because incorrect handling could lead to serious burns. The risk is the probability or chance that the hazard posed by the chemical will lead to injury. Thus, concentrated sulfuric acid is a hazardous chemical, because it is very corrosive and reactive. However, provided it is handled cautiously and with a full understanding of the hazards that it presents, the risks it poses may be small. It is thus evident that hazards are something we can do little about. The hazards posed by a carcinogen, a concentrated acid or an explosive substance are inherent properties of the material. The risks they pose, however, can be (and should be!) minimized by initially preparing a suitable risk assessment, and then by following the procedures laid down in that assessment.