What do extinguishers having a zone of the color blue contain?

Extinguishers with a blue color zone contain powder, specifically dry chemical powder. This type of extinguisher is versatile and effective for fighting multiple classes of fires, including those fueled by flammable liquids and gases, as well as fires involving electrical equipment. The dry powder works by interrupting the chemical reaction of the fire, thus extinguishing the flames.

The blue labeling system helps users quickly identify the type of extinguisher and its intended use in emergency situations, which is crucial for ensuring safety and effective response. This classification reinforces the importance of selecting the appropriate extinguisher based on the fire's source for the best chance of successful extinguishment. Understanding the significance of this color-coding allows for more informed choices in fire safety practices.