A CO₂ (carbon dioxide) fire extinguisher is a specialized firefighting device designed to rapidly control and extinguish fires involving flammable liquids (Class B) and energized electrical equipment (Class C) without leaving any residue or cleanup challenges. The extinguisher works by displacing oxygen around the flame with carbon dioxide gas, effectively smothering the fire and interrupting combustion. Its non-conductive nature makes it safe for use near electrical systems, server rooms, control panels, generators, and machinery.

Constructed with a high-pressure seamless steel cylinder and equipped with a distinctive horn-shaped discharge outlet, CO₂ extinguishers are easy to operate and require minimal maintenance. They are widely used in commercial buildings, offices, hospitals, laboratories, workshops, and industrial facilities where clean fire suppression and protection of electrical equipment are priorities.

In Nepal, CO₂ fire extinguishers are commonly available in 2 kg, 4.5 kg, 5 kg, and larger portable capacities (e.g., 6.5 kg, 9 kg) — providing flexible options for different risk levels and coverage needs. The 2 kg size is suitable for smaller spaces and localized hazards, while 4.5 kg to 5 kg models are popular for offices, commercial premises, and electrical panels. Larger portable CO₂ extinguishers support higher-risk areas with extensive electrical equipment or flammable liquids.

CO₂ fire extinguishers offer rapid response, clean discharge, and reliable performance when dealing with liquid and electrical fire risks, making them an important part of fire safety strategies in both residential and professional environments.