Flash Point - the Mining Quiz List

advertisement
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
Gas-BP -119°f
► -101°f/-75.9°c-°Butane,
► None------
AutoIP 778°f
Answer
► -156°f/-104°c--Propane-Auto
IP 842°f
► -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
Download