634-FIRE-PROTECTION.pdf

634 A&P FIRE PROTECTION SYSTEM (SUBTITLE) FONT STYLE - ARIAL BLACK FONT SIZE - 25  CLASSES OF FIRE Fires are classified into different classes based on the type of material that is burning. Understanding these classes is essential for selecting the appropriat...

634 A&P FIRE PROTECTION SYSTEM (SUBTITLE) FONT STYLE - ARIAL BLACK FONT SIZE - 25  CLASSES OF FIRE Fires are classified into different classes based on the type of material that is burning. Understanding these classes is essential for selecting the appropriate method and extinguisher to combat the fire. Here are the main classes of fire:  Class A: Ordinary Combustibles Description: Fires involving common materials like wood, paper, cloth, rubber, and some plastics. Extinguishing Methods: Water, foam, or dry chemical extinguishers are effective.  Class B: Flammable Liquids and Gases Description: Fires involving flammable or combustible liquids such as gasoline, oil, paint, and solvents, as well as flammable gases. Extinguishing Methods: Carbon dioxide (CO2), foam, or dry chemical extinguishers are suitable.  Class C: Electrical Fires Description: Fires involving energized electrical equipment, such as wiring, circuit breakers, machinery, and appliances. Extinguishing Methods: Non-conductive extinguishing agents like CO2 or dry chemical extinguishers. Never use water.  Class D: Combustible Metals Description: Fires involving combustible metals like magnesium, titanium, potassium, and sodium. Extinguishing Methods: Special dry powder extinguishers designed for metal fires. Water and other common extinguishers are ineffective and can be dangerous.  Class K: Cooking Oils and Fats Description: Fires involving cooking oils and fats, commonly found in commercial kitchens. Extinguishing Methods: Wet chemical extinguishers, which cool and smother the fire while preventing re-ignition.  Class F (Used in Europe and other regions) Description: Equivalent to Class K in the U.S., dealing with cooking oils and fats. Extinguishing Methods: Same as Class K, using wet chemical extinguishers.  Class F (Used in Europe and other regions) Description: Equivalent to Class K in the U.S., dealing with cooking oils and fats. Extinguishing Methods: Same as Class K, using wet chemical extinguishers.  Knowing the class of fire helps ensure that the right extinguisher and method are used, reducing the risk of injury and property damage.  DANGEROUS GOODS Classification of Dangerous Goods Class 1: Explosives Class 2: Gases Class 3: Flammable Liquids Class 4: Flammable Solids Class 5: Oxidizing Substances and Organic Peroxides Class 6: Toxic and Infectious Substances Class 7: Radioactive Material Class 8: Corrosive Substances Class 9: Miscellaneous Dangerous Goods  Packaging and Labeling: Dangerous goods must be properly packaged according to specific standards to prevent leaks, spills, or other incidents during transport. Packages must be clearly labeled with the correct hazard symbols and handling instructions.  Documentation: A Shipper's Declaration is required for dangerous goods, detailing the nature of the goods, the hazards they pose, and how they are packaged. This documentation ensures that all parties involved in the transport process are aware of the risks and can take appropriate precautions.  Restrictions and Prohibitions: Some dangerous goods are strictly prohibited on passenger aircraft and may only be transported on cargo aircraft. Certain items, like lithium batteries, are subject to stringent regulations due to their fire risk. Batteries exceeding 0.3 g lithium metal or 2.7 Wh(WATT HRS) lithium-ion  Training and Compliance: Personnel involved in the transport of dangerous goods must undergo regular training to stay updated on regulations and procedures. Airlines, shippers, and freight forwarders must comply with all applicable regulations to avoid fines, penalties, and potential safety hazards.  OVER HEAT SYSTEM The overheat system in an aircraft is a critical safety mechanism designed to detect and respond to excessive temperatures in specific areas of the aircraft, particularly in the engine compartments, bleed air systems, and other heat-sensitive components.  Temperature Sensors: These sensors are strategically placed in areas prone to overheating, such as engine nacelles, bleed air ducts, and the APU (Auxiliary Power Unit) compartment. The sensors typically include thermocouples, thermal switches, or thermistors that detect abnormal temperature rises. MAGNETIC CHIP DETECTOR  A magnetic chip detector is an electronic instrument that attracts ferromagnetic particles (mostly iron chips). It is mainly used in aircraft engine oil and helicopter gearbox chip detection systems. Chip detectors can provide an early warning of an impending engine failure and thus greatly reduce the cost of an engine overhaul.  Overheat Sensors: Thermocouples: Commonly used in overheat detection systems, these sensors are placed in areas prone to high temperatures, such as the engine compartments, pneumatic ducting, and bleed air systems.  Thermistors: These are temperature-sensitive resistors used in some systems to detect overheat conditions.  Fire Detection Loops: Some overheat systems use fire detection loops that can also detect overheat conditions before they escalate into a fire.  Monitoring Areas: Engines: The engine nacelles and surrounding areas are monitored for excessive heat, as these are critical areas where overheating can lead to catastrophic failures. Pneumatic Ducting: The ducts that carry hot air for various aircraft systems (e.g., environmental control systems) are monitored to ensure they do not overheat and cause damage or fire. Wheel Wells: These areas can overheat due to friction during takeoff and landing, making monitoring crucial for preventing tire or hydraulic fluid fires.  Warning Systems: Cockpit Indicators: Pilots are alerted to overheat conditions via warning lights, alarms, or messages on the aircraft's electronic display systems. These alerts are typically distinct from fire warnings but are treated with similar urgency. Automatic Systems: In some aircraft, if an overheat condition is detected, systems may automatically shut down or isolate the affected area to prevent further damage or fire.  Response Procedures: Pilot Action: Pilots are trained to follow specific procedures when an overheat warning is received. This may involve reducing power to the affected engine, shutting down certain systems, or preparing for an emergency landing. System Isolation: The overheat system may automatically or manually isolate the affected system to prevent overheating from spreading or causing further damage.  Maintenance and Testing: Regular maintenance checks are conducted to ensure that the overheat detection systems are functioning correctly. This includes testing sensors and verifying that alarms and indicators in the cockpit work as intended.  Common Overheat Areas in Aircraft: Engine Nacelles: Particularly near the bleed air valves. Pneumatic Ducting: High-pressure hot air ducts. APU (Auxiliary Power Unit): The compartment housing the APU is monitored for overheating. Hydraulic Systems: Hydraulic lines and reservoirs can overheat under certain conditions.