FIRE HAZARDS , TYPES OF FIRE & FIRE EXTINGUISHERS.pptx

M.PHARMA PHARMACEUTICAL CHEMISTRY 1ST YEAR 2ND SEMESTER MPC204T PHARMACEUTICAL PROCESS CHEMISTRY UNIT 5 INDUSTRIAL SAFETY b) FIRE HAZARDS , TYPES OF FIRE & FIRE EXTINGUISHERS

1. INTRODUCTION FIRE is a rapid oxidation reaction known as combustion, which releases heat, light, and various reaction products. It occurs when a fuel reacts with oxygen in the presence of heat, forming flames. Fire Triangle (Essential Elements for Fire) 1. Fuel – A combustible material (e.g., wood, paper, gasoline). 2. Oxygen – Typically from the air (supports combustion). 3. Heat – Enough energy to reach the ignition temperature. Chemical Reaction of Fire (Combustion) A basic combustion reaction for a hydrocarbon (e.g., methane) is: CH 4 ​ +2O 2 ​ → CO 2 ​ +2H 2 ​O + Heat/Light This reaction releases carbon dioxide (CO₂), water (H₂O), heat, and light. Types of Combustion 1. Complete Combustion – Produces CO₂ and H₂O (blue flame, efficient burning). 2. Incomplete Combustion – Produces carbon monoxide (CO) and soot due to insufficient oxygen (yellow/orange flame).

2. FIRE HAZARD refers to any condition, material, or action that increases the risk of a fire starting or spreading. It can also include anything that makes it difficult to control or extinguish a fire once it begins. Types of Fire Hazards: 1. Electrical Hazards 2. Process And Operation Hazards 3. House Hazards 4. Storage Hazards 5. Smoking Hazards 6. Friction Hazards

3. 1. Electrical Hazards Damaged wiring. Damaged plugs. Wet wires. Broken switches, sockets. Overloaded circuits. Liquid near computers. 2. Process and Operation Related Hazards Cutting and welding operations which use open flame and produce sparks. 3. House Hazards Dry leaves are burn by the sunlight. If gas burner not turn off then there is possibility of explosion.

4. 4. Storage Hazards Flammable or combustible materials stored too close to heat source. Materials stored in damaged container. Materials stored in unlabelled containers. Containers not tightly sealed. 5. Smoking Hazards Ignoring "NO SMOKING" signs. Smoking around flammable or combustible materials. Smoking on bed. Smoking in areas where there is an accumulation of plastic or metal powders that may become explosive. Throwing matches or cigarettes or cigars on table or any other place. 6. Friction Hazards Choking or jamming materials. Poor adjustment of moving parts.

5. Classification of Fire : There are five classes or types of fires : 1. Class A 2. Class B 3. Class C 4. Class D 5. Class K Class A Fire : Fires that involve ordinary combustible materials such as cloth, wood, paper, rubber, paper, rubber, and many plastics. Class B Fire : Fires that involve flammable and combustible liquids such as alcohol, diesel oil, oil-based paints, lacquers etc. and flammable gases. Class C Fire : Fires that involve energized electrical equipment. Class D Fire : Fires that involve combustible metals such as magnesium, titanium, and sodium. Class K Fire : Fires that involve vegetable oils, animal oil, or fats in cooking appliances. This is for commercial kitchens, including those found in restaurants, cafeterias.

6. FIRE EXTINGUISHER is a portable device used to put out small fires by removing one or more elements of the fire triangle (fuel, oxygen, or heat) . Fire can be extinguished by: Cooling : the fuel by removing heat (i.e. by applying water). Smothering : by cutting off oxygen supply (e.g. by application foam, carbon dioxide). Starving : the fire by removing the fuel (e.g. stopping gas flow during a pipeline fire). Inhibition : by stopping the chain reaction (e.g. by applying dry chemical powder). Types of fire extinguishers : There are five types of fire extinguishers - 1. Water extinguisher. 2. Dry chemical/powder extinguishers or foam extinguisher. 3. Carbon dioxide extinguisher. 4. Dry powders (special) extinguisher. 5. Wet chemical extinguisher.

7. 1. Water Extinguishers (Class 'A') : It contains water for use against fires involving ordinary combustibles like paper, wood, cloth and most plastics. 2. Foam/Dry Powder/Chemical Extinguishers (Class ‘B') : In these used dry chemicals to put fires caused by oils, solvents, gasoline, paints, petrol etc. 3. Carbon Dioxide Extinguishers (Class 'C') : It contains carbon dioxide for use against electrical fires. 4. Dry Powder (Special) Extinguishers (Class 'D') : Spray dry powders on combustible metals like magnesium, titanium, sodium, potassium and Al. 5. Wet Chemical Extinguisher (Class ‘K’) : Use a wet, potassium acetate-based, low pH agent to put out "working" fires in which there are animal or vegetable oils and fats. Cooking oil can be hazardous if not used properly. Vegetable oil can catch fire when it becomes too hot. When heating, oils first to start to boil, then will start smoking , and then they will catch on fire e.g. mustard oil etc.

8. How to Use a Fire Extinguisher (PASS Method) 1. Pull the pin – Unlock the extinguisher. 2. Aim at the base of the fire – Not the flames. 3. Squeeze the handle – Release the extinguishing agent. 4. Sweep side to side – Cover the fire area evenly.

9. Fire Detection Devices 1. Smoke Detector 2. Heat Detector 3. Flame Detector 1. Smoke Detector - It is a device that senses smoke, typically as an indicator of fire. It is made up of plastic, shaped like a disk about 150 millimeters (6 inch) in diameter and 25 millimeters (1 inch) thick. It gives very quicker response i.e. within 30-50 sec. It is faster than heat because it responds to smoke generate very early in fire development. 2. Heat Detector - It is a fire detector device. It detects the fires where there is no smoke activated by the significant increase of temperature associated with fire. 3. Flame Detector - It is a sensor designed to detect and respond to the presence of flame and allow flame detection. It reacts to the movement of flame.

10. Prevention Strategy From Fire Hazard : 1. For Electrical Fires – Inspect all wiring, switches, and plugs regularly. All outlets, junction boxes, and electrical panels must have proper cover. Do not connect or disconnect electrical cords or wires with wet hands. Do not overload motor or circuits. Extension, multiple plug adapters are prohibited. 2. For Flammable and Combustible Materials – The cabinets where flammable liquids should be stored are designed in a way that prevents an outside fire from reaching the contents for a period of 10-15 minute. Containers should be tightly sealed when not in use. At least one fire extinguisher are placed in the area. There should be ventilation or exhaust air openings must be arranged to provide air movement directly to the exterior of the building. All ignition sources must be eliminated where flammable liquids are used or stored - Common ignition sources include: Open flames from cutting and welding, matches, heaters, smoking materials, motors, switches, circuit breakers.

11. 3. Gas Cylinder – Oxygen gas cylinders must be at least 20 feet from flammable and combustible materials. Gas cylinder, or any other hazardous materials, cannot be stored in public hall ways or unprotected area. Keep valves closed and put caps on cylinders when not in use. 4. Miscellaneous – For fire prevention some workshop or any other program should be organized in which educate the people i.e. students, senior citizens, landlords, etc. that how to deal with it and prevent fire. 1. For Students : Fire fighters will visit school and teach students the basis of fire prevention. Workshops should be conducted in school for educating students for the effects of fires and how to deal with it and prevent fire. 2. Senior Citizens : It is important that seniors have pre-planned their escape routes and emergency exits.