Flash Point-Ignition Point What? At Work Or At Home
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Flash Point-Ignition Point What? At Work Or At Home
Everyday We Use Chemicals Whether At Work Or In The Home Proper Storage & Understanding How Dangerous Chemicals Can Become If Subjected To Heat Is Using Just Using Good Safety Common Sense.
Flammable Liquids Properties of Flammable Liquids The vapor of a flammable liquid ignites and causes fire or explosion – not the liquid itself. The flammability of a liquid depends on its physical properties: Vapor Pressure Flash Point Limits of Flammability Vapor Density
Flammable Liquids Vapor Pressure Vapor pressure is a measure of how fast a liquid evaporates. The higher the vapor pressure the more rapidly the liquid will evaporate. Vapor pressure goes up and down with the temperature of the liquid. Hydraulic Systems uses oil under pressure to harness the usefulness of chemicals. When System are compromised, hazardous conditions can be magnified.
What is Flash Point? Flash point is the lowest temperature at which a liquid can form an ignitable mixture in air near the surface of the liquid. The lower the flash point, the easier it is to ignite the material. For example, gasoline has a flash point of -40 degrees C (-40 F) and is more flammable than ethylene glycol (antifreeze) which has a flash point of 111 degrees C (232 F).
What Is Ignition Point Ignition point The minimum temperature at which a substance will continue to burn without additional application of external heat. Also called kindling point.
Flammable Liquids Limits of Flammability The limits of flammability is the range that a mixture of air and vapor is flammable. Mixtures can be too lean (not enough vapor) or too rich (too much vapor) to ignite and burn.
Flammable Liquids Flammable Limits Example LEL – “lower explosive limit” UEL – “upper explosive limit”
Flammable Liquids Lower Explosive Limit – LEL In most work situations, the “lower explosive limit” (LEL) is the main concern. Vapors from flammable liquids can be found in the workplace, but are often too diluted to catch fire or explode. However, these vapors can quickly go above the LEL in small room or confined space like a tank.
Flammable Liquids Vapor Density “Vapor density” is a measure of how heavy a vapor is compared to air. Vapors with a density greater than 1.0 are heavier than air and can collect near the floor, and “flow” like a liquid. This may create a fire/explosion hazard if the vapor flows to an ignition source.
Boiling Point Definition Boiling point is the temperature at which a liquid changes to a gas (vapor ) at normal atmospheric pressure. A more specific definition of boiling point is the temperature at which the vapor pressure of a liquid is equal to the external pressure.
Example of Boiling Point Water freezes at 32 F. Turns to liquid at above 32 F. Boils & changes to Gas at 212 F. Expands 17,000 times it normal size when heated.
Boiling Point MSDS relevance Knowing the boiling point of a substance is an important consideration for storage. For example, storing a chemical with a boiling point of 50 C (122 F) in direct sunlight or next to a boiler could cause the material to completely vaporize and/or result in a fire or explosion. Items with a low boiling point generally have a high vapor pressure. Containers of such material can build up significant pressure even when they are below their boiling point. Likewise, low-boiling materials easily produce large amounts of vapor which can be flammable or even explosive.
When Condition Are Just Right Accidents Result A spectacular example of the consequences of introducing a spark to a flammable limit atmosphere occurred in Newcastle in September of 2003. A pipe fitter left an acetylene cylinder inside his vehicle over the weekend. Either the cylinder had a small leak or the valve was not fully closed. The flammable limits for acetylene are extremely broad, 2.5% to 100% in air. Flashpoint is 0 F/-18 C. Boiling point is -119 F/-84 C. When the worker opened the door, an undetermined spark source (the door light switch, light bulb, cellular phone, static etc.) Ignited the mixture with catastrophic results: In the close-up view notice how the roof/door pillars are bent completely sideways. It is amazing that the worker's injuries were confined to his face and ear drums.
What Makes Flash & Ignitions Points Dangerous. Any combustible material such as: solid, liquid, or gas. Most solids and liquids must vaporize before they will burn. Sufficient oxygen must be present in the atmosphere surrounding the fuel for fire to burn.
Flash & Ignition Points Sufficient heat energy must be applied to raise the fuel to it’s ignition temperature. Open flame Sparks and arcs Hot surfaces Friction This reaction can occur when all three of the above elements are present in the proper conditions & proportions.
Extinguishment Theory Remove Heat Remove Fuel Reduce Oxygen WILL Inhibit Chemical Chain Reaction
Proactive Fire Safety Fire Risk Analysis How do we identify potential fire risk?
Proactive Fire Safety Fire Risk Analysis Cont. Identify the fuel source & eliminate it if possible. Identify the heat source and eliminate it if possible. Terminate behaviors that lead to hazardous conditions & replace with appropriate behaviors conducive to good fire safety. 1. Storing flammable and combustible in appropriate areas. 2. On equipment, in fire cabinets, in work areas.
Identifying Fire Hazards In Your Work Area What chemical are present in your work area? What are there flash points? In stationary equipment areas On mobile equipment At shops What heat source are present? Thermal (heat) Electrical Radiant
Do You Know Your Flashpoints? The following is a list of chemicals used on this site, some of these you may even use at home. Do you know how they are stored? At work? At home? See if you know which chemical is which.
Try & Match Flashpoints With The Chemical 247 f/119 c 145 f/78 c 160 f 320 f/160 c 356 f/180 c -49 f/ -45 c 0 f/-18 c -101 f/-75.9 c None -156 f/-104 c -43.7 f/-42 c 79 f 73 f/23 c 175 f Acetylene Gasoline Diesel Fuel Hydraulic 40-wt oil Propane Butane Citrol CRC Contact Cleaner Form Oil Averoe Tree Paint Ethylene Glycol (Antifreeze) Carburetor Cleaner Form Oil CRC Power lube
Did You Choose Right 247 f/119 c------Antifreeze/ Eythlene glycol 145 f/78 c--------
Answer 160 f------Diesel Fuel-IP 500 f 320 f/160 c-----Form Oil 356 f/180 c-----40-wt Hydraulic Oil -49 f/ -45 c----Unleaded Gasoline
Answer 0 f/-18 c----Acetylene 119 f Gas-BP - -101 f/-75.9 c- Butane, 778 f None------ AutoIP
Answer -156 f/-104 c--Propane-Auto 842 f IP -43.7 f/-42 c---- 79 f—Carburetor Cleaner-BP 110 F
Answer 73 f/23 c------------- 175 f----
In Conclusion Any situation that can lead to a fire underground is not good. Let’s all do our part to make sure our work areas are accident free & fire safe. Created By Pat Gazewood