A flammable vapor and air mixture with a specific concentration can explode violently. Vapors are usually heavier than air and will accumulate near the floor or bottom of the hood. The flash point is the minimum temperature at which a liquid emits sufficient vapor to form an ignitable mixture with air near the surface of the liquid. Thus, a solvent with a flash point below room temperature is highly flammable. Flammable liquids are divided into different hazard categories depending on their boiling and flash points.
The National Fire Protection Association (NFPA) and the Globally Harmonized System (GHS) use slightly different categories. A table with examples can be found at the end of this document. Most flammable solvents are defatting to the skin and can be harmful or toxic if inhaled.
Handling Precautions
- Avoid accumulation of vapors and to control sources of ignition including: open flames, electrical equipment, sources of static electricity.
- Accounts of a few of the fires that have occurred in our laboratories may be found in Anecdotes.
- Pouring flammable liquids can generate static electricity. The development of static electricity is related to the humidity levels in the area. Cold, dry atmospheres are more likely to facilitate static electricity. Bonding or using ground straps for metallic or non-metallic containers can prevent static generation.
- Whenever possible use plastic or metal containers or safety cans.
- When working with open containers, use a laboratory fume hood to control the accumulation of flammable vapor.
- Use bottle carriers for transporting glass containers.
- Use equipment with spark-free, intrinsically safe induction motors or air motors to avoid producing sparks. These motors must meet National Electric Safety Code (US DOC, 1993) Class 1, Division 2, Group C-D explosion resistance specifications. Many stirrers, Variacs, outlet strips, ovens, heat tape, hot plates and heat guns do not conform to these code requirements.
- Avoid using equipment with series-wound motors, since they are likely to produce sparks.
- Do not heat flammable liquids with an open flame. Steam baths, salt and sand baths, oil and wax baths, heating mantles and hot air or nitrogen baths are preferable.
- Minimize the production of vapors and the associated risk of ignition by flashback. Vapors from flammable liquids are denser than air and tend to sink to the floor level where they can spread over a large area.
- Electrically bond metal containers when transferring flammable liquids from one to another. Bonding can be direct, as a wire attached to both containers, or indirect, as through a common ground system.
- When grounding non-metallic containers, contact must be made directly to the liquid, rather than to the container.
- In the rare circumstance that static cannot be avoided, proceed slowly to give the charge time to disperse or conduct the procedure in an inert atmosphere.
You can get more training from RCL Safety Centre thru https: www.safetycentre.ng/training_register
At RCL Safety Centre this training is also available in different Nigerian languages like PIDGIN,YORUBA,HAUSA AND IGBO
Our company (RCL Safety Centre) is an indigenous company dedicated to Health, Safety and Environment Training and Services.
We are technical partners of the National Industrial Safety Council of Nigeria (NISCN) as well as approved training partners of most major International Occupational Safety and Health organizations like NEBOSH, and corporate members of ISPON (Institute of Safety Professionals of Nigeria) with thousands of personnel trained in various areas till date.
For more information visit our website: www.safetycentre.ng
Email: sale@safetycentre.ng or mma@safetycentre.ng
Contact us on: 08099700070, 09057666623 or 08164363532