A medium hard and sharp flame is satisfactory in case of LP gas domestic stoves. The flame should meet all the following requirements and if these are achieved, satisfactory combustion may be expected.
1. The burner flame should be entirely blue with no trace of yellow when the utensil is placed on the burner.
2. The inner cone of the flame should be clearly defined.
3. Each individual flame should burn at the port and not lift above it.
4. The outer mantle of the flame should be well defined without lifting or streaming.
5. The flame should ignite readily over the entire burner.