The pour point of any specific fuel is defined as -

Explanation: 

Pour point

The pour point in that temperatures just about which the oil sample will not flow under certain prescribed conditions. In other words, pour point of a liquid is the temperature below which the liquid loses its flow characteristics.

Important Points

• Flash Point: The flash point of a volatile material is the lowest temperature at which vapors of the material will ignite when given an ignition source.
• Fire Point: The fire point of a fuel is the lowest temperature at which the vapor of the fuel will continue to burn for at least 5 seconds after ignition by an open flame. The main difference in fire and flashpoint is that at the flashpoint a substance will ignite briefly, but vapor might not be produced at a rate to sustain the fire.
• Flashpoint and fire points are related to high-temperature characteristics of the fuel and tell the behavior of fuel at high temperatures.
• Cloud Point: Cloud point is the temperature at which oil becomes cloudy or hazy when oil is cooled at a specified rate.
• Pour Point: It is the temperature at which oil just ceases to flow. The pour point of the liquid is the lowest temperature at which it becomes semi-solid and loses its flow characteristics.
• Cloud point and pour point are related to low-temperature characteristics of the fuel and tells the behavior of fuel at low temperatures.