Scott Air-Pak SCBA the freezing point of water at 32 degrees Fahrenheit (0 degrees Celsius) and compare it to 96 °F (35.6 °C; normal human body temperature is 37 °C). While 96 is arithmetically three times 32, the difference in temperature from a scientific point of view is not threefold. Instead of comparing 32 to 96, temperatures of 273.15 K and 308.71 K should be compared. The actual scientifically valid change in temperature from 32 to 96 °F is by a factor of 1.13 (308.71/273.15), not 3. If an air cylinder is pressurized to 4,500 psi at 96 °F and later the temperature
Autoignition temperature in the literature and should only be used as estimates. Factors that may cause variation include partial pressure of oxygen, altitude, humidity, and amount of time required for ignition. Generally the autoignition temperature for hydrocarbon/air mixtures decreases with increasing molecular mass and increasing chain length. The autoignition temperature is also higher for branched-chain hydrocarbons than for straight-chain hydrocarbons. Autoignition temperature The autoignition temperature or kindling point of a substance is the lowest temperature at which it spontaneously ignites in normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the