Oxygen is a colorless, odorless, tasteless gas. The relative density of gas (air=1) at 21.1°C and 101.3kPa is 1.105, and the density of liquid at boiling point is 1141kg/m3. Oxygen is not toxic, but exposure to high concentrations can adversely affect the lungs and central nervous system. Oxygen can be transported at a pressure of 13790kPa as a non-liquefied gas or as a cryogenic liquid. Many oxidation reactions in the chemical industry use pure oxygen instead of air in order to benefit from higher reaction rates, easier product separation, higher throughput or smaller equipment sizes.