University of South Carolina Safety Program Guide
FLAMMABLE AND COMBUSTIBLE LIQUIDS
This Program Guide applies to the storage of flammable and combustible liquids. This guide outlines some of the requirements of the Occupational Safety and Health Administration (OSHA) CFR 1910.106 Flammable and Combustible Liquids. The two primary hazards associated with flammable and combustible liquids are explosion and fire. Safe handling and storage of flammable liquids requires the use of approved equipment and practices per OSHA standards and the National Fire Protection Association (NFPA) 30 Standard.
A good plan for safe use of flammable and combustible liquids contains at least these components:
- Control of ignition sources
- Proper storage
- Fire control
- Safe handling
1. Sources of Ignition:
- Must take adequate precautions to prevent ignition of flammable vapors.
- Some sources of ignition include:
- Open flames
- Static electricity
- Cutting and welding
- Hot surfaces
- Electrical and mechanical sparks
2. Flash Point:
- Flash point means the minimum temperature at which a liquid gives off enough vapor to form an ignitable mixture
- In general, the lower the flash point, the greater the hazard
- Flammable liquids have flash points below 100oF, and are more dangerous than combustible liquids, since they may be ignited at room temperature
- Combustible liquids have flash points at or above 100oF
- Although combustible liquids have higher flash points than flammable liquids, they can pose serious fire and/or explosion hazards when heated
3. Static Electricity:
- Generated when a fluid flows through a pipe or from an opening into a tank
- Main hazards are fire and explosion from sparks containing enough energy to ignite flammable vapors
- Bonding or grounding of flammable liquid containers is necessary to prevent static electricity from causing a spark
- Physically connect two conductive objects together with a bond wire to eliminate a difference in static charge potential between them
- Must provide a bond wire between containers during flammable liquid filling operations, unless a metallic path between them is otherwise present
- Eliminates a difference in static charge potential between conductive objects and ground
- Although bonding will eliminate a difference in potential between objects, it will not eliminate a difference in potential between these objects and earth unless one of the objects is connected to earth with a ground wire
- Always provide adequate ventilation to reduce the potential for ignition of flammable vapors.
7. Storage Fundamentals:
- Identify incompatible chemicals – check the Material Safety Data Sheet
- Isolate and separate incompatible materials
- Isolate by storing in another area or room
- Degree of isolation depends on quantities, chemical properties and packaging
- Separate by storing in same area or room, but apart from each other
8. Storage of Flammable and Combustible Liquids:
- Storage must not limit the use of exits, stairways, or areas normally used for the safe egress of people
- In office occupancies:
Storage prohibited except that which is required for maintenance and operation of equipment
- Storage must be in:
- closed metal containers inside a storage cabinet, or
- safety cans, or
- an inside storage room
9. Safety Cans for Storage and Transfer:
- Approved container of not more than 5 gallons capacity
- Spring-closing lid and spout cover
- Safely relieves internal pressure when exposed to fire
10. Flame Arrester Screen:
- Prevents fire flashback into can contents
- Double wire-mesh construction
- Large surface area provides rapid dissipation of heat from fire so that vapor temperature inside can remains below ignition point
Example of an Approved Container:
11. Storage Cabinets:
- Not more than 60 gal of Class I and/or Class II liquids, or not more than 120 gal of Class III liquids permitted in a cabinet
- Must be conspicuously labeled, “Flammable - Keep Fire Away”
- Doors on metal cabinets must have a three-point lock (top, side, and bottom), and the door sill must be raised at least 2 inches above the bottom of the cabinet
Example of an Approved Storage Cabinet
12. Fire Control:
- Suitable fire control devices, such as small hose or portable fire extinguishers must be available where flammable or combustible liquids are stored
- Open flames and smoking must not be permitted in these storage areas
- Materials which react with water must not be stored in the same room with flammable or combustible liquids
13. Transferring Flammable Liquids:
- Since there is a sizeable risk whenever flammable liquids are handled, OSHA allows only four methods for transferring these materials:
- Through a closed piping system
- From safety cans
- By gravity through an approved self-closing safety faucet
- By means of a safety pump
14. Self-Closing Safety Faucet:
- Bonding wire between drum and container
- Grounding wire between drum and ground
- Safety vent in drum
Example of Self-Closing Safety Faucet and Grounding and Bonding
15. Safety Pump:
- Faster and safer than using a faucet
- Spills less likely
- No separate safety vents in drum required
- Installed directly in drum bung opening
- Some pump hoses have integral bonding wires
16. Waste and Residue:
- Combustible waste and residue must be kept to a minimum, stored in covered metal receptacles and disposed of daily.
17. Safe Handling Fundamentals:
- Carefully read the manufacturer’s label on the flammable liquid container before storing or using it
- Practice good housekeeping in flammable liquid storage areas
- Clean up spills immediately, then place the cleanup rags in a covered metal container
- Only use approved metal safety containers or original manufacturer’s container to store flammable liquids
- Keep the containers closed when not in use and store away from exits or passageways
- Use flammable liquids only where there is plenty of ventilation
- Keep flammable liquids away from ignition sources such as open flames, sparks, smoking, cutting, welding, etc.
- "General." Maintenance and operating practices shall be in accordance with established procedures which will tend to control leakage and prevent the accidental escape of flammable or combustible liquids. Spills shall be cleaned up promptly.
- The two primary hazards associated with flammable and combustible liquids are explosion and fire
- Safe handling and storage of flammable liquids requires the use of approved equipment and practices per OSHA standards
- An excellent reference on this topic is National Fire Protection Association Standard No. 30, Flammable and Combustible Liquids Code
All employees shall be trained prior to use on safe handling and storage of flammable and combustible liquids. Retraining maybe required annual and / or more frequently, based on observed noncompliance of this guide.
Use of Equipment:
A trained and “Competent Person” shall determine requirements and equipment for the safe handling, storage and use of flammable and combustible liquids.
Roles and Responsibilities
- Provide specific training for qualified and compete workers.
- Provide and maintain necessary approved equipment and materials.
- Ensure workers receive training appropriate to their assigned tasks.
- Ensure workers are provided with and use equipment and materials.
- Provide general training.
- Provide assistance with evaluation to determine regulatory requirements and / or best work practices.
- Provide a periodic auditing of work site.
- Attend training.
- Use appropriate safety-related work practices, including all necessary protective equipment and materials.
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