👉 Knock fluid, also known as fire extinguishing agent, is a specialized liquid used to combat certain types of fires, particularly those involving electrical equipment or flammable gases. It works by interrupting the fire triangle—heat, fuel, and oxygen—through a process called endothermic reaction, which absorbs heat and cools the fuel. Knock fluid is typically a mixture of water, carbon dioxide, and other chemicals designed to extinguish Class B (flammable liquids), Class C (electrical equipment), and Class D (metals) fires. Its primary components include water, which cools and dilutes the fire; carbon dioxide, which displaces oxygen and prevents combustion; and inert gases like nitrogen or argon, which displace oxygen. This combination effectively smothers the fire without leaving harmful residues, making it a crucial tool in electrical and industrial fire suppression.
