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Flammable and Combustible Liquids. INSY 3020 Spring 2006. Where do you encounter Flammable Liquids. Gasoline – Car/Truck BBQ Deodorant Sprays/Perfumes. Flammable and Combustible Liquids. 29CFR 1910.106 Based on National Fire Protection Association-NFPA 30 Code
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Flammable and Combustible Liquids INSY 3020 Spring 2006
Where do you encounter Flammable Liquids • Gasoline – Car/Truck • BBQ • Deodorant Sprays/Perfumes
Flammable and Combustible Liquids • 29CFR 1910.106 • Based on National Fire Protection Association-NFPA 30 Code • The standard applies to handling, storage and use of flammable and combustible liquids with flash point below 200F
Definitions Boiling Point • It is the temperature at which the liquid and vapor (gas) phases of a substance can exist in equilibrium • Temp at which vapor pressure = 1 atm
Definitions Vapor Pressure • Partial pressure of the vapors produced at the surface of a liquid at a given temperature (i.e. 100º F) • Remember, it’s the vapor which burns, not the liquid. How will you find the vapor pressure of a liquid?
Definitions Vapor Density • The weight of a flammable vapor compared to air. (Air = 1) Vapor with high density are more dangerous than vapors with low density.
Definitions Relationship between Boiling Point and Vapor Pressure • The boiling point is the temperature at which the vapor pressure of the liquid equals the external pressure
Definitions Flash Point • The minimum temperature at which a liquid gives off enough vapor within a test vessel in sufficient concentration to form an ignitable mixture with air near the surface of the liquid.
How to Determine Flash Point? It is determined by heating the liquid in test equipment and measuring the temperature at which a flash will be obtained when a small flame is introduced above the surface of the liquid.
How will you differentiate between a “flammable liquid” & a “combustible liquid?” • Depends on flash point and vapor pressure/boiling point • Both are properties of materials
200 IIIA COMBUSTIBLE (Flash Point >100 F) 140 II 100 IC 73 FLAMMABLE (Flash Point < 100 F) IA IB 100 Boiling Point (F) Classes of Flammable and Combustible Liquids Flashpoint (Fo)
Flammable Liquids Any liquid having a flashpoint below 100o F (37.8o C) or lower. NFPA Classes IA, IB, & IC Combustible Liquids Any liquid having a flashpoint at or above 100o F (37.8o C). NFPA Classes II & IIIA & B Flammable and Combustible Liquids
Flammable Liquid Classification • Flammable liquids are also called as Class I liquids • Class IA - flashpoints <73 F and boiling point <100 F. • Class IB - flashpoints < 73 F boiling point >=100 F. • Class IC - flashpoints at or above 73 F and below 100 F.
LFL or LEL Lower Flammable Limit (LFL) or Lower Explosive Limit (LEL) The percentage of vapor in the air below which a fire cannot occur. This is because there isn’t enough vapor fuel: mixture is too lean.
UFL or UEL Upper Flammable Limit (LFL) or Upper Explosive Limit (UEL) The percentage of vapor in the air above which a fire cannot occur. This is because there isn’t enough air for the fire: mixture is too rich.
Combustible Liquid Classification Classified among two classes • Class II - shall include those with flashpoints at or above 100 F (37.8 C) and below 140 F (60 C) • Class III - shall include those with flashpoints at or above 140 F (60 C).
Combustible Liquid Classification Class III Classification Class IIIA - shall include those with flashpoints at or above 140 F (60 C) and below 200 F (93.3 C) Class IIIB - shall include those with flashpoints at or above 200 F (93.3 C).
Hazards of Flammable Liquids Exposure Control Measures Include: • Eliminating flames, static electricity, & sparks from electrical circuits. • Temperature. • Proper Ventilation. • Grounding/Bonding. • Spill Control/Emergency Response. • Proper disposal of spent flammable liquids and soaked rags.
Flammable Liquids Fire Prevention Controlling the potential for fire and explosion with flammable liquids is done through: • Housekeeping • Control of ignition sources Remember: STUD- Storage, Transfer, Use and Disposal.
Housekeeping • Establish maintenance and operating practices to control leakage and prevent the accidental release of flammable or combustible liquids • Promptly clean up spills • Maintain adequate aisles for unobstructed movement of personnel and application of fire protection equipment
Housekeeping Combustible waste material and residues must be: • Kept to a minimum • Stored in covered metal receptacles • Disposed of daily • Kept away from unit operations and building areas.
Ignition Sources Sources of ignition can include: • Open flames • Smoking • Cutting and welding • Hot surfaces • Friction heat • Static, electrical, and mechanical sparks • Spontaneous ignition • Radiant heat • Heat producing chemical reactions
Definitions • Grounding: Applying a grounding wire to a container to eliminate a difference in static charge changes the potential between an object and ground. • Bonding: Use of a wire between two drums to eliminate the static charge potential between objects.
Ignition Sources Static charge can be generated when liquids are dispensed and it must be controlled by proper grounding as follows: • The container being filled is connected to the dispensing container with a wire • The dispensing container is connected to a ground wire
Ignition Source: Electrical Equipment Ensure that the electrical equipment is of the correct type: • All electrical wiring and equipment must be installed according to the requirements of Subparts S of OSHA standards • Some areas require special (explosion-proof) electrical equipment
Ignition Sources- Hot work, cutting, welding In order to perform hot work, activities must be planned: • Follow established safe working procedures • Obtain a hot working permit • Must be conducted under the supervision of a qualified competent person
Container & Portable Tank Storage Only approved containers and portable tanks may be used for storage Portable Tanks must have provisions for emergency venting Metal containers and portable tanks should meet the requirements of the Department of Transportation Gases must be stored in a safety can
Storage Cabinets: Design, Construction and Capacity of Containers • Not more than 60 gallons of Class I or II liquids, or 120 gallons of Class III liquids may be stored in the cabinet • Internal temperature must not exceed 325 F when subjected to a 10 minute fire test • Label it is “Flammable-Keep Fire Away”
Storage Cabinets: Design, Construction and Capacity of Containers • The bottom, top, door and sides of metal cabinets must be at least No18 gage sheet metal and double walled with 1.5 inch air space • Doors should have 3 point lock • Door sill raised at least 2” above the cabinet bottom
Storage Equipment Safety Can: An approved red container, of not more than 5 gallons capacity, having a spring-closing lid and spout cover and so designed that it will safely relieve internal pressure when subjected to fire exposure.
Oily waste cans • Oily Waste Can: A self closing metal container used to store rags and cloths soaked in flammable liquid • Protects fires from spontaneous combustion, sparks and careless use of smoking material
Oily waste cans: Design, Construction and Capacity of Containers • The lid opens no more than 60 degrees and remains closed when not in use • Isolates rags and oil from fire sources and limits oxygen to eliminate spontaneous combustion. • Round construction and elevated bottom encourage circulation of air around can to disperse heat and reduce moisture build-up and rusting.
Plunger Cans: Design, Construction and Capacity of Containers • Dispense flammable liquids and solvents safely, without waste or exposure. • Help you quickly and easily moisten cleaning cloths or swabs. • The perforated pan screen serves as a flame arrester.
Storage rooms • Must comply with NFPA • 6 air changes/hr required by NFPA • Rooms must be liquid tight where the walls join the floor • Storage room must meet the standard methods of fire test by NFPA
Storage Rooms: Design, Construction and Capacity of Containers • Floors in storage area at least 4” below the surrounding floor • Rooms must be liquid tight • Aisle at least 3’ wide • Containers over 30 gallons must not be stacked
Storage Rooms: Ventilation • 6 complete air changes/hour required by NFPA • Every inside storage room must be provided with either a gravity or a mechanical exhaust ventilation system
Storage Inside Building • Flammable or combustible liquid drums shall not be stored so as to limit use of exits, stairways, or areas normally used for the safe egress of people. • The storage of such liquids in containers or portable tanks is prohibited in office occupancy areas • Leaking containers shall be removed to a storage room or a safe location outside and the contents transferred to an undamaged container.
Incidental Storage (Small quantities) Liquids located outside of storage cabinets/areas shall not exceed: 25 Gallons of Class IA in containers. 120 Gallons of Class IB, IC or Class II liquids in containers.
Safe Storage Practices • No open flames, smoking, sparks or welding is allowed in flammable liquid storage areas. • Store in a cool location. Not outside in direct sunlight. The warmer the flammable liquid is the more vapors it generates! • Storage shall be in an open or well ventilated area.
Safe Storage Practices • Do not store need oxidizers. • Drums of flammable liquid shall be grounded. • A 10 lbs. fire extinguisher shall be readily accessible within the storage area.
Getting Information How do you get information about hazardous chemicals? • You can get information two ways: • from the product label, • from the product material safety data sheet. MSDS
Getting Information What is a material safety data sheet? • Material safety data sheets or “MSDSs” are information sheets on products that: • tells what chemicals are in the product, • what the hazards of the chemicals are, • how to protect yourself from the hazards. MSDS
Material Safety Data Sheet MSDS – what information do they have? • Names of hazardous chemicals in a product, • Physical and chemical properties of the product, • Physical hazards of working with the product, • Health hazards of working with the product (including signs and symptoms of overexposures), Acetone Flammable & highly volatile Burns Headaches, eye irritation
Material Safety Data Sheet • The main way the chemical enters the body, • The legal limit allowed in the air • If the chemical is a carcinogen • Precautions for safe use of the hazardous chemical, Inhalation 750 ppm No Use with adequate ventilation, keep away from open flame