You can use the fire extinguisher to green
The pressure indicator of a fire extinguisher is actually a special pressure gauge. An instrument that measures and indicates higher than ambient pressure by means of an elastic element as a sensing element.
Some types of fire extinguishers (pressure extinguishers) are filled with high pressure gases. It acts as a jet power for extinguishing substances (such as dry powder). To indicate the internal gas pressure condition of the extinguisher, an accumulator pressure indicator is attached to the pressure extinguisher except the carbon dioxide extinguisher.
The green range of the extinguisher pressure indicator is the normal work area.A fire extinguisher is a portable fire extinguisher. Fire extinguishers are placed with chemicals to fight fires. It is one of the common fire protection facilities. Different types of fire extinguishers contain different components, which are designed for different fire alarms.