MAY 9, 2015
SPRINGFIELD, MASS. (WWLP)
Springfield residents were evacuated from their homes
following a large industrial fire at 115 Stevens Street.
Two trailers with magnesium chips caught fire, which quickly
spread to a tractor trailer nearby. This fire started around midnight and
burned for nearly two hours. Smoke was billowing out of the Joseph
Freedman scrap metal factory on Stevens Street.
When magnesium catches fire, it’s not easy to put out.
Springfield Fire Department spokesman Dennis Leger told 22News that
firefighters had to contain the flames until they burned out.
This quickly turned into a two alarm fire and residents were
evacuated from Stevens Street and Eureka Street. Police had this entire
area blocked off until the fire was eventually extinguished around 2:00 a.m.
22News arrived after noticing flames from I-91 near the
Basketball Hall of Fame and spoke with some of those frightened neighbors.
Aaron Buffany said “I heard like a big wash of fire come up,
I ran outside and the blaze was like 70 feet in the air. I was very, very
scared”.
Many people reported hearing explosions, which was likely
from the burning metal itself.
Junius Gabriel told 22News, “We didn’t think it was nothing,
and then all of the fire trucks and police cars came flying down in the street.
You can see all of the black smoke over all of those houses right there, and
then all of a sudden a big cloud came up”.
Dennis Leger said the fire didn’t spread to any buildings or
homes, but since magnesium burns so hot, it was extremely difficult to put
out. Fortunately, no one was hurt and homeowners were allowed back inside
just after 2:00 Saturday morning.
Source: WWLP.com
//------------------------/////
Magnesium is a combustible metal, however, it can be
melted and processed without incident by following well developed safety
practices.
In certain forms, like a thin ribbon, magnesium ignites quite easily. In solid forms, such as magnesium ingots, combustion is difficult to get started.
Magnesium is an excellent conductor of heat, and, as a practical matter, the entire piece must be brought to a temperature near the melting point before ignition will occur. Normally, this will not occur unless the solid magnesium piece is surrounded by a general conflagration from other sources.
Care must be exercised with magnesium when it is:
· in a molten state;
· in a finely divided form, such as chips, granules, or powder;
· involved in a general conflagration.
Molten magnesium
Safety clothing and equipment
Molten magnesium, like any other substance at 600 ºC, will cause severe burns upon contact with your skin. Those who work around molten magnesium must wear adequate protective clothing and equipment. This includes:
· safety glasses;
· hard hat with safety shield;
· fire retardant clothing;
· safety shoes;
· insulated gauntlet gloves.
All safety clothing and equipment should be tested to ensure that the protection is adequate.
First aid provisions should include fire blankets and safety showers. All personal protective equipment should meet applicable statutory codes.
Protection of the melt
Molten magnesium will ignite and burn when exposed to air, so it must be protected during the melting operations. The traditional method was a cover of chloride salts that fluidized, excluding air contact at the surface. Common practice today, although not universal, is to use a protective gas, such as sulfur hexafluoride, in very low concentrations with air – or air and carbon dioxide.
Sulfur hexafluoride, or SF6, forms a film on the melt surface, which prevents excessive oxidation.
Gas feeding system
The gas feeding system should be designed to prevent high concentrations of sulfur hexafluoride over the melt because it will severely corrode the steel cover and pot. The corrosion product can react with molten magnesium and could cause an explosion.
The system design should ensure minimal effect from air flow disturbing the gas blanket. Fuel supply lines should have combustion safety controls and remote shut offs.
Prevent contact with water
Automatic sprinklers should not be installed over melting operations, heat treating furnaces, or in areas where magnesium in a finely divided form is produced or stored.
If water comes into contact with any molten magnesium, whether it is in the foundry furnace or a puddle in a burning building, there could be an explosion. The water will expand to 1,000 times its original volume and, in so doing, may throw molten metal a considerable distance. In addition, magnesium's great affinity for oxygen will dissociate the water, releasing flammable hydrogen which can be explosive when mixed with air.
Pre-heat ingots and tools
Any material, such as ingots or tools, that are introduced into molten magnesium must be pre-heated well above 100 ºC to drive off all moisture or other volatiles. Any cold surface should be suspected of containing moisture condensed from the atmosphere.
Keep melting pot clean
Molten magnesium can react exothermically with iron oxide in a thermite reaction which generates temperatures in excess of 2200 ºC and a large amount of heat.
Since most magnesium melting pots are made of steel, it is extremely important to keep the inside of the pot clean and free of scale. Likewise, scale should be removed regularly from the furnace to prevent a reaction with molten magnesium in the event of a pot failure.
The refractories used for the furnace should be high alumina or magnesia since molten magnesium can react violently with even small amounts of silica which may be present in ceramic materials.
Run-out pans should be provided in the event of a pot failure and they should be kept clean and free of moisture and scale at all times.
Fire extinguishing materials
Dry, Class D fire extinguishing materials, such as G-1 powder and foundry flux, should always be kept nearby.
Foundry structure
Magnesium foundry structures should be built with non-combustible materials and the floors around melting operations should be hard burned or vitreous paving block. The heat from molten magnesium can release the water of hydration in concrete which will cause it to spall, sometimes explosively.
Summary: molten magnesium
While handling of molten magnesium requires care and certain precautions, many producers and foundries worldwide routinely melt and process thousands of tons each year without incident by strictly adhering to well proven safety practices.
Finely divided forms
Magnesium in finely divided form is readily ignitable and can ignite spontaneously in the presence of water or cutting fluids containing fatty acids. Hydrogen will also be produced, introducing an explosion hazard in addition to fire.
Airborne magnesium dust will burn with explosive violence if ignited in the critical air-dust ratio. Smoking and the use of open flame or electrical welding must be prohibited in areas where magnesium is being machined, sawed, or ground. All electrical connections and motors must be explosion proof. Non-sparking conductive tools must be used where magnesium dust may be present.
Dust collector system
Grinding dust should be captured in a wet dust collector system that is dedicated to magnesium only. The entire system should be grounded and the power supply to the exhaust fan and the liquid level controller should be inter-locked.
The system should be designed to avoid dry dust accumulation at any point before being converted to sludge, and avoid dry dust containing any high speed moving parts. The collector must also be designed so that hydrogen generated in the sludge is vented at all times, even in the event of a power failure.
No magnesium should be ground that has a chromated surface or contains steel inserts because both can spark. Sparks from any source can ignite the grinding dust and the resulting fire can travel through the entire system.
Sludge from the liquid separators should be removed at least daily and transported to the disposal site or staging area in covered and vented steel drums.
Machining magnesium
Machining of magnesium requires less power than any of the other commonly used metals, allowing for maximum speeds and feeds that produce large chips. Cutting tools should be kept sharp and never allowed to ride on the metal without cutting. Dull tools and idling could produce enough heat to ignite the turnings.
Magnesium storage and transportation
Magnesium in any product form should be stored at ground level in a well drained area where water will not puddle. Preferred storage for ingots and parts is a single level, non-combustible building, but this may not be practical in all cases. If stored with other combustible materials, the National Fire Protection Association recommends the following volumes of magnesium:
· parts weighing 11 kg or more: limit to 36 cubic meters;
· parts weighing less than 11 kg: limit to 28 cubic meters.
Automatic sprinklers recommended
Unlike areas where molten metal is present, automatic sprinkler systems are strongly recommended in ingot or parts storage areas since their operation may prevent the magnesium from becoming involved in a fire originating in nearby combustible materials.
Aisles should be wide enough to permit effective use of equipment by fire fighters.
Powder, chips, granules, and turnings
Dry magnesium powder, chips, granules, and turnings should be stored in tightly sealed, non-combustible containers such as steel drums that are well separated from other combustible materials. The use of automatic sprinklers in those areas should be prohibited.
Wet magnesium turnings, fines, or sludge should be kept under water in a covered and vented non-combustible container and stored outdoors. When damp magnesium is exposed to air, it will generate heat which accelerates the evaporation and will eventually result in ignition. Containers should never be stacked, and ignition sources should be kept away from the vent.
Transporting magnesium
Most industrialized nations classify particulate magnesium as "hazardous" material which must be regulated when transported by air, rail, highway, or water. The regulations usually cover packaging, shipping documents, labeling, and placarding. Be sure to check your country for compliance, or, if shipping internationally, secure a copy of the United Nations' publication, "Recommendations on the Transport of Dangerous Goods."
If there is a fire
Magnesium fires are spectacular because they give off a bright light and billowing clouds of white smoke. The white smoke is magnesium oxide which, by itself, is non-toxic, but inhalation should be avoided since excessive amounts can produce metal fume fever symptoms. One must also recognize the possibility that toxic fumes from other sources could be in the smoke.
Your best chance to control any fire is to catch it while it is young, and magnesium is no exception. Fires in dry magnesium particulate will burn rather slowly and evenly, but can flare up quickly if disturbed – or if moisture or cutting oils are present.
Smothering agents
Magnesium burns by direct oxidation and so the only way to control a magnesium fire is to "smother" it with dry, air-excluding agents – or let it burn to extinction. Faced with a fire that is out of control, firefighters may have to resort to damage control of adjacent structures.
Suitable "smothering agents" for magnesium fires are:
· Dry G-1 Powder;
· Met-L-X Powder;
· Magnesium Foundry Flux;
· Proprietary Materials that are specific to magnesium.
In confined areas, such as a storage tank, magnesium fires may be suppressed with argon.
Never use water on a magnesium fire
Water should never be used on a magnesium fire because the water will dissociate into oxygen and hydrogen, accelerating the fire and creating an explosion hazard.
Many conventional extinguishing agents will also accelerate a magnesium fire, including:
· foam;
· carbon dioxide;
· halogenated agents;
· certain dry chemicals containing mono or diammonium phosphate;
· sand.
The latest agent added to the product line of safety products by the TLI Group for the fire protection industry, changes the way fires can now be safely extinguished. Now high temperature fires can be extinguished in any type of weather. No longer does the fire fighter have to stand within five to eight feet of a high temperature fire in order to extinguish it. The FEM-12 SC extinguisher allows the fire fighter a range of 30 to 40 feet from the source of the fire. The FEM-12 SC also presents an agent that is an environmentally safe alternative for the industry. In addition, the fire fighter no longer has to worry about breathing clouds of dust. FEM-12 SC can now extinguish those high temperature vertical fires safely, and quickly. There is little threat of the material reigniting. Also, the fire fighter no longer has to stand over the fire for over 30 minutes to see if it is going to reignite after applying a dry powder agent. The fire fighter can now move on without worry and extinguish other areas of concern.
Applications include metal fires, such as magnesium and titanium used in aircraft brake assemblies and landing gear components. Other applications include rubber tires, aircraft engines, magnesium rims; and other structural components of the aircraft such as fiber glass, composite materials, and composite materials with honeycomb aluminum.
The extinguishing elements of the FEM-12 SC work to reduce high temperature fires rapidly, and quickly. It coats the burning material to help in preventing reignition. Because it is a liquid vertical fires can now be successfully fought where previously dry powder was ineffective.
This material has passed the U.S Federal Aviation Administrations testing requirements for aquatic toxicity (American Society for Testing and Materials International - ASTM #E 729-96 reapproved 2002, with range finding test according to the U.S. Environmental Protection Agency; and American National Standards Institute - ANSI/UL 711 Rating and Testing of Fire Extinguishing Section 10.2 and 10.2.28.) These tests where conducted by the United States Air Force Research Laboratory for the U.S. FAA.
For further information go to www.tligroup.com or Google “tn06/26” to see a white paper jointly issued by the United States FAA and the U.S. Air Force Research Laboratory.
Employee training & response team
If you are manufacturing, processing, or storing magnesium, then you must train all operating personnel on safe procedures and have a skilled in-house emergency team.
There is a legal requirement in a number of countries that you must notify your local fire department if you are processing or storing magnesium and a joint plan developed for emergency response. This should be done regardless of any legal requirements.
Summary
Magnesium will burn, particularly in a molten state or in finely divided forms.
Magnesium can react with water to produce hydrogen, resulting in a fire or explosion. However, with proper safeguards, you can prevent fires or explosions.
The use of magnesium is growing rapidly on a worldwide basis and it is a fact that millions of tons of magnesium have been melted and processed without incident by following well developed safety practices.
In certain forms, like a thin ribbon, magnesium ignites quite easily. In solid forms, such as magnesium ingots, combustion is difficult to get started.
Magnesium is an excellent conductor of heat, and, as a practical matter, the entire piece must be brought to a temperature near the melting point before ignition will occur. Normally, this will not occur unless the solid magnesium piece is surrounded by a general conflagration from other sources.
Care must be exercised with magnesium when it is:
· in a molten state;
· in a finely divided form, such as chips, granules, or powder;
· involved in a general conflagration.
Molten magnesium
Safety clothing and equipment
Molten magnesium, like any other substance at 600 ºC, will cause severe burns upon contact with your skin. Those who work around molten magnesium must wear adequate protective clothing and equipment. This includes:
· safety glasses;
· hard hat with safety shield;
· fire retardant clothing;
· safety shoes;
· insulated gauntlet gloves.
All safety clothing and equipment should be tested to ensure that the protection is adequate.
First aid provisions should include fire blankets and safety showers. All personal protective equipment should meet applicable statutory codes.
Protection of the melt
Molten magnesium will ignite and burn when exposed to air, so it must be protected during the melting operations. The traditional method was a cover of chloride salts that fluidized, excluding air contact at the surface. Common practice today, although not universal, is to use a protective gas, such as sulfur hexafluoride, in very low concentrations with air – or air and carbon dioxide.
Sulfur hexafluoride, or SF6, forms a film on the melt surface, which prevents excessive oxidation.
Gas feeding system
The gas feeding system should be designed to prevent high concentrations of sulfur hexafluoride over the melt because it will severely corrode the steel cover and pot. The corrosion product can react with molten magnesium and could cause an explosion.
The system design should ensure minimal effect from air flow disturbing the gas blanket. Fuel supply lines should have combustion safety controls and remote shut offs.
Prevent contact with water
Automatic sprinklers should not be installed over melting operations, heat treating furnaces, or in areas where magnesium in a finely divided form is produced or stored.
If water comes into contact with any molten magnesium, whether it is in the foundry furnace or a puddle in a burning building, there could be an explosion. The water will expand to 1,000 times its original volume and, in so doing, may throw molten metal a considerable distance. In addition, magnesium's great affinity for oxygen will dissociate the water, releasing flammable hydrogen which can be explosive when mixed with air.
Pre-heat ingots and tools
Any material, such as ingots or tools, that are introduced into molten magnesium must be pre-heated well above 100 ºC to drive off all moisture or other volatiles. Any cold surface should be suspected of containing moisture condensed from the atmosphere.
Keep melting pot clean
Molten magnesium can react exothermically with iron oxide in a thermite reaction which generates temperatures in excess of 2200 ºC and a large amount of heat.
Since most magnesium melting pots are made of steel, it is extremely important to keep the inside of the pot clean and free of scale. Likewise, scale should be removed regularly from the furnace to prevent a reaction with molten magnesium in the event of a pot failure.
The refractories used for the furnace should be high alumina or magnesia since molten magnesium can react violently with even small amounts of silica which may be present in ceramic materials.
Run-out pans should be provided in the event of a pot failure and they should be kept clean and free of moisture and scale at all times.
Fire extinguishing materials
Dry, Class D fire extinguishing materials, such as G-1 powder and foundry flux, should always be kept nearby.
Foundry structure
Magnesium foundry structures should be built with non-combustible materials and the floors around melting operations should be hard burned or vitreous paving block. The heat from molten magnesium can release the water of hydration in concrete which will cause it to spall, sometimes explosively.
Summary: molten magnesium
While handling of molten magnesium requires care and certain precautions, many producers and foundries worldwide routinely melt and process thousands of tons each year without incident by strictly adhering to well proven safety practices.
Finely divided forms
Magnesium in finely divided form is readily ignitable and can ignite spontaneously in the presence of water or cutting fluids containing fatty acids. Hydrogen will also be produced, introducing an explosion hazard in addition to fire.
Airborne magnesium dust will burn with explosive violence if ignited in the critical air-dust ratio. Smoking and the use of open flame or electrical welding must be prohibited in areas where magnesium is being machined, sawed, or ground. All electrical connections and motors must be explosion proof. Non-sparking conductive tools must be used where magnesium dust may be present.
Dust collector system
Grinding dust should be captured in a wet dust collector system that is dedicated to magnesium only. The entire system should be grounded and the power supply to the exhaust fan and the liquid level controller should be inter-locked.
The system should be designed to avoid dry dust accumulation at any point before being converted to sludge, and avoid dry dust containing any high speed moving parts. The collector must also be designed so that hydrogen generated in the sludge is vented at all times, even in the event of a power failure.
No magnesium should be ground that has a chromated surface or contains steel inserts because both can spark. Sparks from any source can ignite the grinding dust and the resulting fire can travel through the entire system.
Sludge from the liquid separators should be removed at least daily and transported to the disposal site or staging area in covered and vented steel drums.
Machining magnesium
Machining of magnesium requires less power than any of the other commonly used metals, allowing for maximum speeds and feeds that produce large chips. Cutting tools should be kept sharp and never allowed to ride on the metal without cutting. Dull tools and idling could produce enough heat to ignite the turnings.
Magnesium storage and transportation
Magnesium in any product form should be stored at ground level in a well drained area where water will not puddle. Preferred storage for ingots and parts is a single level, non-combustible building, but this may not be practical in all cases. If stored with other combustible materials, the National Fire Protection Association recommends the following volumes of magnesium:
· parts weighing 11 kg or more: limit to 36 cubic meters;
· parts weighing less than 11 kg: limit to 28 cubic meters.
Automatic sprinklers recommended
Unlike areas where molten metal is present, automatic sprinkler systems are strongly recommended in ingot or parts storage areas since their operation may prevent the magnesium from becoming involved in a fire originating in nearby combustible materials.
Aisles should be wide enough to permit effective use of equipment by fire fighters.
Powder, chips, granules, and turnings
Dry magnesium powder, chips, granules, and turnings should be stored in tightly sealed, non-combustible containers such as steel drums that are well separated from other combustible materials. The use of automatic sprinklers in those areas should be prohibited.
Wet magnesium turnings, fines, or sludge should be kept under water in a covered and vented non-combustible container and stored outdoors. When damp magnesium is exposed to air, it will generate heat which accelerates the evaporation and will eventually result in ignition. Containers should never be stacked, and ignition sources should be kept away from the vent.
Transporting magnesium
Most industrialized nations classify particulate magnesium as "hazardous" material which must be regulated when transported by air, rail, highway, or water. The regulations usually cover packaging, shipping documents, labeling, and placarding. Be sure to check your country for compliance, or, if shipping internationally, secure a copy of the United Nations' publication, "Recommendations on the Transport of Dangerous Goods."
If there is a fire
Magnesium fires are spectacular because they give off a bright light and billowing clouds of white smoke. The white smoke is magnesium oxide which, by itself, is non-toxic, but inhalation should be avoided since excessive amounts can produce metal fume fever symptoms. One must also recognize the possibility that toxic fumes from other sources could be in the smoke.
Your best chance to control any fire is to catch it while it is young, and magnesium is no exception. Fires in dry magnesium particulate will burn rather slowly and evenly, but can flare up quickly if disturbed – or if moisture or cutting oils are present.
Smothering agents
Magnesium burns by direct oxidation and so the only way to control a magnesium fire is to "smother" it with dry, air-excluding agents – or let it burn to extinction. Faced with a fire that is out of control, firefighters may have to resort to damage control of adjacent structures.
Suitable "smothering agents" for magnesium fires are:
· Dry G-1 Powder;
· Met-L-X Powder;
· Magnesium Foundry Flux;
· Proprietary Materials that are specific to magnesium.
In confined areas, such as a storage tank, magnesium fires may be suppressed with argon.
Never use water on a magnesium fire
Water should never be used on a magnesium fire because the water will dissociate into oxygen and hydrogen, accelerating the fire and creating an explosion hazard.
Many conventional extinguishing agents will also accelerate a magnesium fire, including:
· foam;
· carbon dioxide;
· halogenated agents;
· certain dry chemicals containing mono or diammonium phosphate;
· sand.
The latest agent added to the product line of safety products by the TLI Group for the fire protection industry, changes the way fires can now be safely extinguished. Now high temperature fires can be extinguished in any type of weather. No longer does the fire fighter have to stand within five to eight feet of a high temperature fire in order to extinguish it. The FEM-12 SC extinguisher allows the fire fighter a range of 30 to 40 feet from the source of the fire. The FEM-12 SC also presents an agent that is an environmentally safe alternative for the industry. In addition, the fire fighter no longer has to worry about breathing clouds of dust. FEM-12 SC can now extinguish those high temperature vertical fires safely, and quickly. There is little threat of the material reigniting. Also, the fire fighter no longer has to stand over the fire for over 30 minutes to see if it is going to reignite after applying a dry powder agent. The fire fighter can now move on without worry and extinguish other areas of concern.
Applications include metal fires, such as magnesium and titanium used in aircraft brake assemblies and landing gear components. Other applications include rubber tires, aircraft engines, magnesium rims; and other structural components of the aircraft such as fiber glass, composite materials, and composite materials with honeycomb aluminum.
The extinguishing elements of the FEM-12 SC work to reduce high temperature fires rapidly, and quickly. It coats the burning material to help in preventing reignition. Because it is a liquid vertical fires can now be successfully fought where previously dry powder was ineffective.
This material has passed the U.S Federal Aviation Administrations testing requirements for aquatic toxicity (American Society for Testing and Materials International - ASTM #E 729-96 reapproved 2002, with range finding test according to the U.S. Environmental Protection Agency; and American National Standards Institute - ANSI/UL 711 Rating and Testing of Fire Extinguishing Section 10.2 and 10.2.28.) These tests where conducted by the United States Air Force Research Laboratory for the U.S. FAA.
For further information go to www.tligroup.com or Google “tn06/26” to see a white paper jointly issued by the United States FAA and the U.S. Air Force Research Laboratory.
Employee training & response team
If you are manufacturing, processing, or storing magnesium, then you must train all operating personnel on safe procedures and have a skilled in-house emergency team.
There is a legal requirement in a number of countries that you must notify your local fire department if you are processing or storing magnesium and a joint plan developed for emergency response. This should be done regardless of any legal requirements.
Summary
Magnesium will burn, particularly in a molten state or in finely divided forms.
Magnesium can react with water to produce hydrogen, resulting in a fire or explosion. However, with proper safeguards, you can prevent fires or explosions.
The use of magnesium is growing rapidly on a worldwide basis and it is a fact that millions of tons of magnesium have been melted and processed without incident by following well developed safety practices.