What extinguishing materials are used for Class B and C fires?
What types of fires can be extinguished with carbon dioxide (CO2) fire extinguishers? Class B fires which involve flammable liquids and gases, solvents, oils, greases (excluding cooking oils/greases in depth) tars, oil-based paints and lacquers. Class C fires which involve energized electrical equipment.
What kind of materials can Class C extinguisher be used for?
Fire extinguishers with a Class C rating are suitable for fires in “live” electrical equipment. Both monoammonium phosphate and sodium bicarbonate are commonly used to fight this type of fire because of their nonconductive properties.
What is the symbol for a Class C fire?
Class C extinguishers do not have a numerical rating. The C classification means the extinguishing agent is non-conductive. The geometric symbol indicating Class C is a blue circle. Class D fire extinguishers are commonly found in a chemical laboratory.
What is Class C material?
Class C – Flame-spread 76-200, smoke developed 0-450. NFPA 101 primarily applies this classification to interior wall and ceiling finish materials. Roof coverings must meet a different set of criteria.
What is a Class C roof?
Class C roof assemblies are those that are effective against light fire-test exposure. Class C roof assemblies and roof coverings shall be listed and identified as Class C by an approved testing agency.
Is plywood a Class C finish?
Many interior finishes, including wood-based ma- terials, are hygroscopic, and their moisture content can affect flame spread performance. Lumber, plywood, and other wood-based materials typically fall into Class B or Class C when tested and evaluated in accordance with ASTM E84.
What is a Class B finish?
Class B includes materials with flame-spread ratings between 25 and 75, and smoke test ratings below 450. Class C includes flame spreads from 76 to 200, and still limits smoke ratings to below 450. For example, labeled wood that has been treated with fire retardant usually qualifies as a Class A interior finish.
What does ASTM stand for?
American Society for Testing Materials