Glass Grenade Style Fire Extinguisher “Bombs:” Are They Safe?
Posted by Em Ironstar on November 10th, 2016
Glass Grenade Style Fire Extinguisher “Bombs:” Are They Safe?
Kathleen Watkin (MAS Advisor)
Emma Morris (Community Engagement Coordinator)
Wendy Fitch (MAS Executive Director)
What are Glass Grenade Style Fire Extinguisher “Bombs?”
Glass Grenade Style Fire Extinguisher “Bombs” are glass bulbs (shaped a little like an incandescent light-bulb) filled with an unknown liquid. These types of fire extinguishers were made and used between the years of 1870 and 1910. They would be stored on metal brackets on the wall. If there was a fire, any person young or old would be able to take it out of the holder, and throw it at the fire. The fire would either be put out by it, or it would help to manage the fire enough for the person to escape the flames.
The earliest glass fire-suppression devices or "fire grenades" were hand-blown, patterned, often colored, round glass bottles, usually filled with salt water until about 1900. After the 19th century, the fancy blown glass began to disappear and a more industrial design prevailed, with smooth, frosted or clear glass. The liquid in the clear glass often had a blue or red coloring agent. In most of the more recent devices, a fire suppression chemical usually carbon tetrachloride (CTC) was used.
In addition to being able to be thrown at the fire, the more recent fire grenades usually had a bracket assembly that suspended them directly over areas of particular fire risk, like boilers and furnaces. If high temperatures reach some styles of brackets, it would release the grenade that would then crash and shatter, releasing the fire suppression liquid. Others had heat-activated, spring-loaded triggers that would break the bottom seal, spilling the liquid onto a deflector that would distribute it over a larger area.
Why are they dangerous?
When the Industrial designed fire extinguishers were made they were unaware of the health hazards that are caused by exposure CTC. Exposure for more than fifteen minutes can lead to respiratory, gastrointestinal, kidney, thyroid, brain, reproductive and developmental problems; which lead to death in many cases. When CTC is exposed to the heat of a fire, it can produce phosgene gas, a chemical weapon used in WWI.
When experts began to understand the long-term and negative health effects of this chemical, as well as how CTC and other chemicals like it – such as Chlorofluorocarbons (CFCs) – were beginning to harm the atmosphere, the chemical began to be phased out of production. The production of CTC has dwindled since the effects were discovered, most noticeably since the 1980s.
How should the Museum “Treat” Glass Grenade Style Fire Extinguisher “Bombs?”
First, Read the Label! If you are luckily enough to have a Grenade Style Fire Extinguisher that has salt water in it, you can carefully display the artifact using supports or a display case to prevent damage.
If the label states it’s contains a fire suppressant or the label is illegible or missing, there are three options you can take to ensure the safety of the artifact and the people who interact with it.
Destroy the Artifact
The Museum Association of Saskatchewan HIGHLY ADVISES the you can have the artifact destroyed. After deaccessioning the artifact from the collection, contact your local Police and Fire Department to see if they are able to safety handle destroying the artifact. If they are unable to help you, Envirotec Services Incorporated based out of Saskatoon and Regina has helped other museums in Saskatchewan for a cost.
Estimate for disposal by Envirotec Services Incorporated
Pricing includes the travel to site and collection of Carbon Tetrachloride bulbs. These are Estimates only including hourly cost not the actuals which would include the truck and technician time and will depend upon distance from Regina or Saskatoon to the museum and the return trip back to the Envirotec facility to process the chemical.
*Actual cost may vary depending on amount of chemical.
If the museum decides to mount the fire extinguisher on a wall using its original brackets with support or creating new brackets, then ensure the space chosen is high enough to prevent easy access and the space is large enough so a secondary mount can be created and placed around the extinguisher. A Plexiglas box should be created and mounted around the fire extinguisher, as well.
If the museum is planning to place the fire grenade inside a display-case or into storage, The Western Development Museum Conservation department advises that a custom made mount be created. In a custom mount the fire extinguisher would be nestled in a custom made cushion which prevents it from moving around and accidently braking. This mount should be made from carved museum quality ethafoam, that is then covered Tyvek to cushion the mount against any rough edges created carving the ethafoam. The glass Fire Extinguisher should be tied using Tyvek ties or archivally safe string into its mount if it is on display. If in storage, a lid should also be included. The Western Development Museum advices that the Workplace Hazardous Materials Information System (WHMIS) and fragile labels be clearly affixed on the mount.
Drain the Bulb
Draining the bulb of its contents is also an option. A conservator using a fume hood in laboratory conditions, creates a small hole by piercing the bottom of the bulb and that whatever fluid is in it is allowed to drip out safely. This process MUST be completed by a trained professional and conducted in a laboratory in a fume hood to ensure the safety of everyone involved. Elisabeth Trudell of the Wetaskiwin & District Heritage Museum, explains the steps involved in this process here: http://wetaskiwinmuseum.com/?p=1101
For More Information, See:
“GFL Environmental.” GFL Environmental. 2019. Website: http://gflenv.com/gfl-locations/saskatoon/
P.O. Box 25055, Saskatoon, Saskatchewan S7K 8B7
100 Cory Road, East Cory Industrial Park, RM of Corman Park, Saskatchewan
Tel. (306) 244-9500
P.O. Box 27063, Regina, Saskatchewan S4R 0J0
2B Industrial Drive, Great Plains Industrial Park, Emerald Park, Saskatchewan
Tel. (306) 721-9500
Kibbel III, William. “Common Fire Safety Devices in Old Home a Health Hazard.” Old House Web: Ideas & Advice for Old House Enthusiast.” 2016. Website: http://www.oldhouseweb.com/how-to-advice/common-fire-safety-device-in-old-homes-a-health-hazard.shtml
Ma, Kevin. “Artifacts Under Cover.” St. Alberta Gazette. Sunday, December 8, 2012. Website: http://www.stalbertgazette.com/article/20121208/SAG0801/312089987/
Trudell, Elisabeth. “Extinguishing Danger: Putting out the Potential Hazards of Carbon Tetrachloride.” Wetaskiwin & District Heritage Museum. July 31, 2015. Website: http://wetaskiwinmuseum.com/?p=1101
“Carbon Tetrachloride.” Agency for Toxic Substance & Disease Registry. March 3, 2011. Website: http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=35
Stop, Drop & Roll (or Throw): Fighting Fires with Fire Grenades
Most active firefighting technologies throughout history have tended to require teams of firefighters and involve close proximity to danger. Buckets, pumps, hoses and extinguishers, while effective, only work when those employing them are willing to directly engage daunting walls of flame. For hundreds of years, however, another technology has evolved in parallel, designed in part to allow firefighters to keep their distance from infernos: the fire grenade.
The first known patent for a fire extinguishing device was awarded in 1723 to Ambrose Godfrey, an English chemist. Unlike modern point and shoot extinguishers, his gadget was intended to be thrown or rolled into fires. It was made for use in buildings as well as on ships, consisting of a cask of fire-extinguishing liquid and a pewter chamber loaded with (yes, of all things) gunpowder. A lit fuse ignited the powder and the resulting explosion would scatter the solution across a blaze. All in all, it was a quite literal manifestation of “fighting fire with fire.”
England at the time (and densely-packed London in particular) was prone to periodic infernos, and the country had evolved various techniques and technologies to combat these, including handheld pumps, fire hoses and fire engines. Most of these systems, though, relied on ready sources of water and teams of human operators willing to get and stay close to the flames. Godfrey wanted to supplement this arsenal with a weapon that could be kept closer at hand and would be easier for a single individual to deploy.
To demonstrate the efficacy of his device, Godfrey erected a three-story wooden house, adding pitch, oil, branches and twigs to “increase the fury of the flames, which were suffered to rise to their utmost height.” According to reports, the test building was set aflame and his device hurled into the first floor, extinguishing the blaze almost immediately. The inventor described the workings of his new gizmo as follows:
“The new method … consists of gunpowder closely confined, which as soon as animated by fire acts by its elastic force upon a proper medium (water impregnated with a certain preparation) and divideth it instantly into millions of millions of the most minute and imperceptible atoms, which with equal violence and swiftness are immediately forced into the innermost recesses of the flames.”
Godfrey’s device was sold and used for a time, though it did not, as he had perhaps hoped, obviate the need for more labor- and water-intensive approaches. When the modern spray extinguisher was patented in 1818, extinguishing grenades largely disappeared for several decades.
Then, in the late 1800s and early 1900s, a more compact and sophisticated type of the fire grenade began to take off. For a few decades, glass fire suppression spheres could be found all over in homes, schools, factories, even in cars and on trains. These globes contained firefighting chemicals like carbon tetrachloride and were designed to compact conventional or electrical fires.
Some were made to break on impact, while others featured spring-loaded triggers that would melt and break the glass when heated.
Versions of these new type of fire grenade were made by a variety of manufacturers, including the Harden Hand Grenade Fire Extinguisher Company, Acme Fire Extinguisher, Red Comet and Little Giant.
Unfortunately, the carbon tetrachloride liquid used in many of these contraptions is not only toxic to humans on its own, but also converts into a dangerous gas when exposed to extreme heat: phosgene, a deadly chemical weapon used in the first world war. In turn, when exposed to water (that stuff also commonly used to combat fires), phosgene breaks down into hydrochloric acid (corrosive to the touch) and carbon dioxide (that stuff humans prefer to breath out, not in).
With the rise of modern fire extinguishers and sprinkler systems (and in light of aforementioned chemical dangers), fire grenades once again became a lesser-used technology for most of the 20th Century.
Today, a number of (less-problematic) grenade-style extinguishers are still used, generally designed to open up or self-destruct when they encounter fire and disperse dry chemical powder over the flames.
Some of these devices are made to be actively thrown or rolled by users, breaking on impact or fitted with time-delay triggers like conventional grenades. With products like F.I.T. (Fire Interruption Technology), the user pulls a pin and lobs the device into a fire.
Other fire balls are used in passive suppression systems. These are spread out around buildings and detonated in the presence of extreme heat, like sprinkler systems but with less infrastructural overhead (no need to worry about pipes, water pressure or complex systems).
Sometimes, brave firefighters are called upon to run into burning buildings in order to save people. In most cases, though, fire engines with high-pressure hoses (along with some modern-day fire grenades) are there to help firefighters maintain a safe distance from the flames.
Even with the sophisticated technologies firefighters have today, perhaps there is still room for an even more compact and long-distance weapon in their arsenal, like launchers that fire (or drones that drop) an explosive new version of the ever-evolving fire grenade.
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No Fire in the Hole!: Firefighters Use Flame-Retardant Grenades
A new grenadelike gadget—designed to quickly extinguish flames in small quarters, thereby limiting injury to victims as well as firefighters—is becoming an important part of firemen's arsenals.
More than 37 fire departments along the U.S. east coast now carry Vancouver-based ARA Safety's FIT-5 (for fire interruption technology). The device, available to firefighters since December, is a means of knocking down or even extinguishing fires in rooms, basements and attics. The FIT-5 (price tag: around $1,300) is a nine-pound (four-kilogram) red disk that resembles a land mine and is deployed like a grenade: A firefighter pulls its cord and tosses the disk into the area engulfed in flames; within seconds the FIT-5 releases a wispy cloud of potassium carbonate, a flame retardant that suppresses combustion and disrupts fire at the molecular level.
The company says the device can fully extinguish a class B (fuel-based) fire in a room 2,100 cubic feet (60 cubic meters) or less and reduce fire temperatures from 1,000 to 300 degrees Fahrenheit (540 to 150 degrees Celsius) in less than 10 seconds. The FIT-5 is also designed to control class A (wood-based) fires enough so that firefighters can douse them with water. Firefighters in New York State and New Jersey have successfully contained three fires (in a room on the third floor of a house and two in basements) with the FIT-5 since it hit the market.
The FIT-5 is designed to be most effective in a contained space—the larger the area, the less effective, which is why it is not a good candidate for squelching, say, wildfires.
Most handheld fire extinguishers sold at hardware stores for home use are pressurized with nitrogen or carbon dioxide to propel powdery potassium bicarbonate, liquid water or a fluorocarbon at a fire. In addition to allowing firefighters to control fires from a safe distance, the FIT-5 could also replace halon fluorocarbons, an effective fire-fighting tool until they were banned in 1994 after it was discovered that they destroy Earth's ozone layer.
Because halon displaces oxygen, it extinguished electrical, grease and other fires that water alone could not, says Robert Kaul, ARA Safety's technical director. When a firefighter approaches a fire and pulls the rip cord located on the side of the FIT-5 device, this generates a spark of heat that leads to a thermal reaction within the FIT-5. Within 10 seconds the container releases a white cloud of potassium carbonate aerosol that expands to fill an enclosure (room, basement, attic). A FIT-5 grenade is unlikely to leak and works when wet because it is not pressurized and has a sealed outer casing that keeps moisture out. In addition, even if the rip cord is not pulled, the device will automatically dispense the when placed in temperatures exceeding 500 degrees F (260 degrees C).
"Once the FIT-5 is done, you're left with potassium carbonate powder, which can be vacuumed or swept clean," says Michael Gardner, ARA Safety's director of marketing.
Of course, potassium carbonate, used in the production of soap and glass, must be handled carefully; it can be dangerous if inhaled (by irritating the respiratory tract and causing coughing and shortness of breath) or swallowed, potentially damaging the gastrointestinal tract and causing nausea, vomiting and diarrhea. The odorless chemical can also severely irritate the eyes or skin if it comes in contact with either.
Andrew Schmidt, chief of Morris County, N.J.'s Jefferson Township Fire Department (about 45 miles northwest of New York City) used a FIT-5 in April to contain a basement fire in the nearby town of West Milford. Because most of the fire departments in the area are volunteer, Schmidt was unable to marshal much of a firefighting squad at 3 P.M., when most of his volunteers were working their day jobs. On arriving at the burning basement, he broke one of the windows and tossed in an FIT-5, which held the flames in check until the fire trucks arrived.
"When you don't have a truck, and you don't have water, you've got to do something," he says, adding that West Milford ended up using less than 200 gallons (750 liters) of water to extinguish a fire that easily could have required 6,000 gallons (22,700 liters) to put out. Schmidt was so impressed that he has become trainer and consultant for ARA Safety.
The company is now exploring developing a larger version of the device and hopes to within the next year offer a fixed system for homes and businesses that could be mounted on a wall or ceiling like a smoke detector and switched on when needed. This would be particularly useful in rooms containing lots of computers or other electronic equipment that would be ruined if water was used to douse the flames.
ABOUT THE AUTHOR(S)
Larry Greenemeier is the associate editor of technology for Scientific American, covering a variety of tech-related topics, including biotech, computers, military tech, nanotech and robots.
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Vintage Fire Grenades History and Value
During the 19th and into the first part of the 20th century nothing provoked a deadlier fear than fire. Cities from coast to coast suffered major fire calamities. San Francisco, Chicago, New York and Boston were each plagued with several large fires.
The earliest defenses were leather buckets, filled with water and transferred from hand-to-hand, with each then thrown onto the flames. These were followed by a wheeled apparatus, fitted with a hand operated pump, forcing water through a hose and onto a fire.
These were ways to combat fires in buildings, but what defense was available to the average citizens to defend themselves when a small fire broke out within the home. Within minutes, small fires leaped into roaring conflagrations.
Homes and buildings contained plenty of fodder to feed a fire, and several sources for ignition. Candles, kerosene and oil lamps, open fireplaces and wood and coal stoves were all triggers for combustion.
And as for the fodder, non-fire-retardant bedding and clothing, as well as combustible building materials, once ignited, would fuel a fire. Those waiting for the bucket brigade or the volunteer pumper force watched as buildings were engulfed in flames.
From the 1870s through the early 1900s, when a small fire broke out in the interior of the home, a glass orb known as a fire grenade was taken from a wall-mounted-bracket or kept handy next to the fireplace and thrown at the base of the flames. The grenades were filled, in some cases, with salt water (used because it would not freeze in the winter cold), others were filled with carbon tetrachloride and sealed with a cork and cement. The concept was simple; the glass orb shattered on contact and the contents, as it spewed onto the flames, vaporized into fire extinguishing gas.
The First Fire Grenades
According to some historians, the fire grenade had its roots reaching back to time of the Roman Empire. Back then there were no bucket brigades or fire hoses. Some defense against fire was needed; buildings were equipped with primitive fire grenades.
The American Civil War was an incubator for new inventions and innovations, and it was during this time the idea of a fire grenade was resurrected. In 1863, the first patent for the fire grenade was awarded. (Several more patents would follow in later years.) In a burgeoning industrial nation such as America, when a market opened requiring goods or services, there was no shortage of manufacturers to provide them. Several companies exploded onto the scene to fill that niche.
The companies used powerful metaphors as a marketing tool. Red Comet was marketed as “the Original Automatic Fire Extinguisher.” The company based in Littleton, Colorado, cornered a large piece of the market with their trademark red orbs. ‘AutoFyrStop’ of Philadelphia touted their extinguishers as both automatic and ornamental. And with a name like ‘Shur Stop’ how could their fire extinguisher grenade fail to do the job. But in several cases, they were ineffectual and did fail. They were helpful when a fire was just breaking out; beyond that stage, it was mostly a futile attempt to douse hungry flames.
[Related Article: American Fire Marks]
S.F. Hayward, located on Broadway in New York City, found many customers among the city’s residents for their ‘Hand Fire Grenade.’ Harden’s Star Fire Grenade was one of the most popular brands. Fire grenades were made of thin glass, allowing it to shatter easily; some were plain glass orbs, while others were embossed with designs; bands, medallions and quilting gave a more ornamental look.
Some even resembled cut crystal—a perfect accessory for the Victorian mantle. A rainbow of colors was available; varying shades of aqua, amber and clear, others were green and cobalt blue; these last two colors are more highly sought after. A number of the grenades were only 4 inches tall, but as a rule, the grenades, including a narrow neck, were between 6 and 8 inches tall.
The Larkin Company
The Larkin Company produced fire grenades that were filled with an extinguishing powder, instead of liquid contents, which was released in a swinging motion over the flames.
The grenade manufacturers weren’t shy about claims attested to in their advertisements. Text highlighted the popularity and effectiveness of their products. Hayward’s made effective use of illustrations in their newspaper advertisements. In one such example, two young girls were confidently attacking a fire, in what appears to be the parlor of a Victorian era home, with the grenade extinguishers, although the blaze appeared out of control; the text below stating with the use of their grenade; “….fire cannot exist for a moment.” The price, $10 per dozen. Another popular illustration depicted a watchman, armed with a basket, similar to those used in carrying milk bottles, filled with fire grenades, attacking a fire he discovered while on his rounds. Production of fire grenades tapered off after 1905 with the advent of the modern brass and copper fire extinguishers.
The glass extinguishers were manufactured well into the 1950s. It wasn’t until 1954 that NFPA (National Fire Protection Association) stated in its Fire Protector Handbook that the “hand grenade fire extinguisher was no longer acceptable to the Underwriters Laboratory.” Aside from the dangers from broken glass, the carbon tetrachloride decomposed at high temperatures producing a toxic gas, Phosgene.
Collecting vintage fire grenades
Vintage fire grenades hold an attraction for many collectors. Those interested in collecting glass would enjoy these rather unusual fire extinguishers, for their variety of shapes and sizes; common shapes were bulbous, teardrop and round; they could also be in the form of a rolling pin. Collecting pieces from specific manufacturers holds great appeal; some of the rather ornate models address the interests of those fancying Victorian items. Their vivid colors and interesting shapes allow them to display well. And there are those engrossed in the broad spectrum of antique fire fighting items.
Although not found in as high numbers as other types of glass containers; many were destroyed in fighting home and factory fires, they can still be found at antique shops; and occasionally at flea markets and yard sales. Some have been discovered, while clearing out old factories, barns and garages. But a caveat; many of those that are sealed could still be filled with toxic liquid chemical contents. Examples might be found at a live auction; and most assuredly, they are offered on eBay. And don’t forget bottle shows. They are a great place not only to purchase fire grenades, but are also an excellent source of information on the subject.
Reproduction fire grenades
Reproductions, as with any collectible, can be a problem but there are things to look for. Those that are not authentic are, many times, made of thicker glass. Does it look too perfect? Maybe the lip is too smooth, or on some, the seam runs the entire length of the glass grenade, whereas the originals might have applied necks with the seam stopping at the shoulders of the piece.
Some reproductions are not intended to deceive and are sold as such. One example: Reproduction Harden’s Star Fire Grenade Extinguishers are marked with the letter “R” on the base. Of course, you always want to know who you are buying from.
Fire grenade values
Prices might start as low as $25 for a Red Comet and range higher to $2,000 and more for more rare examples. eBay seller skutz9741 was offering a AutoFyrStop fire grenade with original mounting bracket, frosted glass, complete with labels for an opening bid of $50. A mint S.F. Hayward Hand Fire Grenade that sits a bit over 6 inches was listed by eBay seller, tundra09. The piece is a deep amber color and has embossed diamond-shaped medallions on two sides; containing the message, “Patented August 8, 1871, 407 Broadway, New York.” eBay seller badge83 realized $102.50 for a beautiful aquamarine 8-inch-tall, Harden Fire Grenade Extinguisher with its trademark five-pointed star embossed within a large circle.
A number of the grenades were produced in France; a beautiful example was offered by German eBay seller, mallaubzustaub605. This 6-inch-tall amber model was manufactured in Paris and marketed under the brand of L’Incustomable and has four embossed circles. This particular extinguisher is still sealed with its original reservoir of salt water inside. On www.antiquebottletrader.com, two fire grenades were offered for sale. One is of French manufacture, light yellow amber in color, with four embossed circles on shoulders. The price is $275. The other is a mint dark cobalt blue made by Harden’s; almost 7 inches tall for $300.
Broadsides such as one from 1885, advertise the Hayward Hand Grenade Fire Extinguisher, for specific use in factories, hotels and other public buildings (they were even used on trains) average between $15 to $50; this particular sheet carries an illustration of a watchman discovering a fire while carrying a wire basket, filled with the glass extinguishers, on his rounds. He is depicted throwing a grenade onto the fire.
Fire grenade is a fitting name for this type of fire extinguisher; it was meant to be tossed just as one would lob a military grenade. The title of a 1985 article in the L.A. Times summed up the success of fire grenades; “Fire Grenade Wasn’t So Hot At Its Job.”
Learn more about fire grenades
For those wishing to learn more about fire grenades there are two publications that might be helpful; Digger O’Dell’s Fire Grenade and Target Ball 2011 Price Guide, and the Fire Grenade Price and Information Guide, by Albrecht and Feldhaus.
Related Content: Identifying Old Bottles
David McCormick holds a master’s degree in Regional Planning from the University of Massachusetts. He was employed by the City of Springfield, Mass., for several years. Now retired, McCormick works as a freelance writer whose articles have appeared in Naval History, Elks Magazine and Wild West Magazine.
Fire grenade modern
Fire grenades and aerosol mist: Launching new fire suppression tools
From the earliest days of “put the wet stuff on the red stuff,” there’s been the search for the next best thing in extinguishing agents. This has been especially true for the protection of high value fixed facilities once it became apparent that automatic fire sprinklers could exact more damage on the property (e.g., communications equipment and electronics) than the heat and smoke from a fire. And that quest created a domino effect of products, from Halon to “fire grenades” and condensed aerosol mist.
THE USE – AND BAN – OF HALON
In 1954, the U.S. Army and DuPont collaborated to develop Halon 1301 to provide fire suppression capabilities for high-value military assets (e.g., aircraft, mainframe computers and telecommunication switching centers) as total flooding systems. Halon (short for halogenated hydrocarbon) was a liquefied gas used to extinguish fires by chemically interrupting the combustion chain reaction – the fourth side of the fire tetrahedron.
Halon, in its various forms, was an extremely popular extinguishing agent because it was nonconducting and left no residue after being discharged. In fact, Halons were popularly described as a "clean” extinguishing agent.
Fixed fire suppression systems using Halon 1301 and its halogenated hydrocarbon “cousin,” Halon 1211, made their first entries into non-military fire suppression applications in the 1960s, quickly gaining traction with facility managers charged with protecting high-value assets. And with many of those assets containing sensitive electronics and computer technologies, assets that would be damaged or destroyed by the activation of a traditional fire sprinkler system, Halons quickly became the “gold standard” for the protection of such facilities.
In 1987, representatives from around the world met and developed an international treaty, The Montreal Protocol on Substances that Deplete the Ozone Layer, which quickly became known as the Montreal Protocol. The goal of the treaty was to gradually eliminate the production and consumption of ozone-depleting substances to limit their damage to the earth’s ozone layer.
The United States was among the 197 countries to sign the Montreal Protocol – the first treaty in the history of the United Nations to achieve universal ratification – and has been a leader in guiding the successes of the treaty. In 1994, the U.S. EPA banned the production and import of Halons 1211 and 1301 to comply with the Montreal Protocol, prompting chemists and fire protection engineer around the world to begin the search for a suitable replacement for Halon in fire suppression systems.
SPREAD THE WORD: CONDENSED AEROSOL MIST
One Halon alternative that is gaining in popularity are fire suppression systems that use condensed aerosol mist (CAM), defined by NFPA 2010: Standard for Fixed Aerosol Fire Suppression Systems (2020 Edition) as “an extinguishing medium consisting of finely divided solid particles, generally less than 10 microns in diameter, and gaseous matter, generated by a combustion process of a solid aerosol-forming compound.”
Upon activation in fire suppression systems using CAM, an extinguishing aerosol mist is created by electric or thermal ignition of a specialized solid that produces micron-size dry chemical particulates and gases that mix to create a uniform aerosol.
There are myriad positives to the use of CAM for fire suppression in enclosed spaces:
- Zero ozone depletion potential, meaning they don't contribute to global warming.
- Included in the EPA Significant New Alternatives Policy program as acceptable substitutes for Halon 1301 as a total flooding agent.
- Extinguishing capability three times that of Halon 1301.
- No oxygen depletion: CAM suppresses fires at exceptionally low concentrations by interfering with the fire's free radicals, making the atmosphere safer for firefighters and any trapped occupants.
- Reduces interior temperature in the space quickly, providing increased victim survivability and less heat stress for firefighters.
Most commonly, those condensed aerosol particulates consist of potassium carbonate (K2CO3) that result from the thermal decomposition of a solid aerosol-forming compound that includes potassium nitrate as an oxidizer. In addition to being effective, fire suppression systems using CAM are easier to install, maintain and operate in part because there are no pressurized cylinders or propellant gases required because the pyrogenic generation of CAM provides sufficient energy for a rapid discharge and efficient distribution.
CAM: HOW IT WORKS
The CAM is self-generated upon activation of the system. Manufacturers and installers for many fire suppression systems using CAM (e.g., Pyrogen, Ltd. and FirePro) create systems that consist of a series of canisters containing the solid aerosol-forming compound being strategically placed within the risk area and electrically connected to most types of manual or automatic fire control panels. When heat/flame detectors identify a credible fire threat, the system identifies those canisters that need activation and then sends an electrical current to the canister(s), which ignites the aerosol-forming compound.
CAM has proven to be effective in extinguishing fires, particularly those involving hydrocarbon-based materials, such as gasoline, diesel fuel, hydraulic liquid, lubricants, natural gas and wood. The micron-size aerosol particles exhibit gas like 3D qualities that allow the agent to rapidly distribute throughout an enclosure and reach into the most concealed and shielded locations.
NOT JUST FOR FIXED FACILITIES
Fire suppression systems using CAM are extremely scalable and cost-effective, making their installation possible for practically any civilian application, in many cases using a pre-packaged kit, that include, but are not limited to:
- Marine applications protecting engine rooms, machinery spaces and cargo holds on commercial vessels, barges and tow boats, plus civilian watercraft (e.g., power boats, yachts, and sail boats).
- Automotive applications protecting automobiles, trucks, trailers, RVs, and emergency vehicles (e.g., fire apparatus and ambulances), as well as commercial vehicles like motor coaches and buses and just about anything with four wheels!
- Aviation applications for the protection of general aviation aircraft and helicopters as well as cargo bays, ground support equipment, and maintenance shops for commercial aviation.
LAUNCHING FIRE GRENADES INTO THE TOOLBOX
Manufactures such as Fireway, Inc. and AFG Flame Guard USA have taken CAM technology and put it into a portable unit for use by firefighters and other public safety personnel and civilians. While those manufacturers, and others, may refer to their products as a "fire suppression generator" or “CAM generator,” I’m sure the term fire grenade is catchier with firefighters.
The Stat-X First Responder from Fireway is a compact, lightweight canister unit that’s small enough that it can be carried on a person’s belt (using a holster designed for that purpose). For instantaneous fire suppression, the user pulls the actuator and tosses it into an enclosed space where a fire’s located (just like pulling the pin on a grenade and hurling it toward the enemy!). And it’s small enough that it can be tossed up or down stairs, even through a second-floor window (depending on one’s arm strength and aim!).
The X-Tinguish X-Treme from Flame Guard weighs in at 13 lbs., including the weight of the compound, but isn’t much bigger than were some of the first handheld thermal imaging cameras. But its larger size gives it more fire suppression “punch,” as it can effectively “mist” an enclosed area of roughly 5,300 cubic feet.
When used by first-arriving firefighters aboard fire apparatus, these devices can buy time for fire attack handline set-up, impede flashover and provide an emergency egress route for occupants seeking to exit the structure. This can provide a valuable fire suppression tool for under-staffed volunteer fire departments providing more time for enough firefighters to arrive to conduct safely conduct fire suppression operations.
USE BY OTHER PUBLIC SAFETY AGENCIES
In many communities, especially those relying on volunteer-staffed fire department for fire suppression, a law enforcement officer or EMT/paramedic may be the first person to arrive at a working structure fire. If that officer or EMS member has a portable CAM generator (fire grenade), they could use it to slow a fire long enough to enable occupants to get out and allow fire departments assets to arrive.
Consider this scenario. An ambulance (not staffed by firefighters) arrives at a vehicle fire resulting from an accident. There are occupants trapped in the burning vehicle and the fire department has not yet arrived. An EMT or paramedic could break a window, toss a CAM generator into the vehicle to knock down the fire and remove the occupants. Or this scenario: An ambulance arrives first at the scene and encounters an early-stage fire. After evacuating people, and before fire apparatus can arrive and set up for operations, one of the ambulance crew members pulls the actuator on a Stat-X First Responder, or activates a X-Tinguish X-Treme, and tosses it into the room where they see the fire.
AED for fire
Long ago we learned that fog pattern fire streams are more effective on a fire in an enclosed space, and that’s the case with fire grenades as well. That's because the confinement keeps the aerosol mist from dissipating so that it can keep "mixing it up" with those free radicals.
With that caveat, I don’t see any objective arguments for to not have these fire suppression units carried by public safety agencies. Think of them as the AED for a fire.
I foresee the fire grenade becoming a cost-effective alternative to fire extinguishers for a few reasons:
- Reduced maintenance requirements (e.g., annual inspection like those for fire extinguishers);
- Keeps distance between user and fire; and
- Minimal user training required.
I'm all in for anything that helps firefighters do their jobs more safely, effectively and efficiently. Let's not forget Firefighter Life Safety Initiative 8: Utilize available technology wherever it can produce higher levels of health and safety. From my point of view, that means getting fire grenades into the hands of not just firefighters but all members of public safety agencies who could find themselves in the position of first-arriving first responder.
Active fire protection device
"Extinguisher" redirects here. Extinguisher may also refer to a candle snuffer.
A fire extinguisher is an active fire protection device used to extinguish or control small fires, often in emergency situations. It is not intended for use on an out-of-control fire, such as one which has reached the ceiling, endangers the user (i.e., no escape route, smoke, explosion hazard, etc.), or otherwise requires the expertise of a fire brigade. Typically, a fire extinguisher consists of a hand-held cylindrical pressure vessel containing an agent that can be discharged to extinguish a fire. Fire extinguishers manufactured with non-cylindrical pressure vessels also exist but are less common.
There are two main types of fire extinguishers: stored-pressure and cartridge-operated. In stored pressure units, the expellant is stored in the same chamber as the firefighting agent itself. Depending on the agent used, different propellants are used. With dry chemical extinguishers, nitrogen is typically used; water and foam extinguishers typically use air. Stored pressure fire extinguishers are the most common type. Cartridge-operated extinguishers contain the expellant gas in a separate cartridge that is punctured prior to discharge, exposing the propellant to the extinguishing agent. This type is not as common, used primarily in areas such as industrial facilities, where they receive higher-than-average use. They have the advantage of simple and prompt recharge, allowing an operator to discharge the extinguisher, recharge it, and return to the fire in a reasonable amount of time. Unlike stored pressure types, these extinguishers use compressed carbon dioxide instead of nitrogen, although nitrogen cartridges are used on low temperature (–60 rated) models. Cartridge operated extinguishers are available in dry chemical and dry powder types in the U.S. and in water, wetting agent, foam, dry chemical (classes ABC and B.C.), and dry powder (class D) types in the rest of the world.
Fire extinguishers are further divided into handheld and cart-mounted (also called wheeled extinguishers). Handheld extinguishers weigh from 0.5 to 14 kilograms (1.1 to 30.9 lb), and are hence, easily portable by hand. Cart-mounted units typically weigh more than 23 kilograms (51 lb). These wheeled models are most commonly found at construction sites, airportrunways, heliports, as well as docks and marinas.
The first fire extinguisher of which there is any record was patented in England in 1723 by Ambrose Godfrey, a celebrated chemist at that time. It consisted of a cask of fire-extinguishing liquid containing a pewter chamber of gunpowder. This was connected with a system of fuses which were ignited, exploding the gunpowder and scattering the solution. This device was probably used to a limited extent, as Bradley's Weekly Messenger for November 7, 1729, refers to its efficiency in stopping a fire in London.
A portable pressurised fire extinguisher, the 'Extincteur' was invented by British Captain George William Manby and demonstrated in 1816 to the 'Commissioners for the affairs of Barracks'; it consisted of a copper vessel of 3 gallons (13.6 liters) of pearl ash (potassium carbonate) solution contained within compressed air. When operated it expelled liquid onto the fire.
Thomas J Martin, a Black inventor, was awarded a patent for an improvement in the Fire Extinguishers on March 26, 1872. His invention is listed in the U. S. Patent Office in Washington, DC under patent number 125,603.
The soda-acid extinguisher was first patented in 1866 by Francois Carlier of France, which mixed a solution of water and sodium bicarbonate with tartaric acid, producing the propellant CO2 gas. A soda-acid extinguisher was patented in the U.S. in 1881 by Almon M. Granger. His extinguisher used the reaction between sodium bicarbonate solution and sulfuric acid to expel pressurized water onto a fire. A vial of concentrated sulfuric acid was suspended in the cylinder. Depending on the type of extinguisher, the vial of acid could be broken in one of two ways. One used a plunger to break the acid vial, while the second released a lead stopple that held the vial closed. Once the acid was mixed with the bicarbonate solution, carbon dioxide gas was expelled and thereby pressurized the water. The pressurized water was forced from the canister through a nozzle or short length of hose.
The cartridge-operated extinguisher was invented by Read & Campbell of England in 1881, which used water or water-based solutions. They later invented a carbon tetrachloride model called the "Petrolex" which was marketed toward automotive use.
The chemical foam extinguisher was invented in 1904 by Aleksandr Loran in Russia, based on his previous invention of fire fighting foam. Loran first used it to extinguish a pan of burning naphtha. It worked and looked similar to the soda-acid type, but the inner parts were slightly different. The main tank contained a solution of sodium bicarbonate in water, whilst the inner container (somewhat larger than the equivalent in a soda-acid unit) contained a solution of aluminium sulphate. When the solutions were mixed, usually by inverting the unit, the two liquids reacted to create a frothy foam, and carbon dioxide gas. The gas expelled the foam in the form of a jet. Although liquorice-root extracts and similar compounds were used as additives (stabilizing the foam by reinforcing the bubble-walls), there was no "foam compound" in these units. The foam was a combination of the products of the chemical reactions: sodium and aluminium salt-gels inflated by the carbon dioxide. Because of this, the foam was discharged directly from the unit, with no need for an aspirating branchpipe (as in newer mechanical foam types). Special versions were made for rough service, and vehicle mounting, known as apparatus of fire department types. Key features were a screw-down stopper that kept the liquids from mixing until it was manually opened, carrying straps, a longer hose, and a shut-off nozzle. Fire department types were often private label versions of major brands, sold by apparatus manufacturers to match their vehicles. Examples are Pirsch, Ward LaFrance, Mack, Seagrave, etc. These types are some of the most collectable extinguishers as they cross into both the apparatus restoration and fire extinguisher areas of interest.
In 1910, The Pyrene Manufacturing Company of Delaware filed a patent for using carbon tetrachloride (CTC, or CCl4) to extinguish fires. The liquid vaporized and extinguished the flames by inhibiting the chemical chain reaction of the combustion process (it was an early 20th-century presupposition that the fire suppression ability of carbon tetrachloride relied on oxygen removal). In 1911, they patented a small, portable extinguisher that used the chemical. This consisted of a brass or chrome container with an integrated handpump, which was used to expel a jet of liquid towards the fire. It was usually of 1 imperial quart (1.1 l) or 1 imperial pint (0.57 l) capacity but was also available in up to 2 imperial gallons (9.1 l) size. As the container was unpressurized, it could be refilled after use through a filling plug with a fresh supply of CTC.
Another type of carbon tetrachloride extinguisher was the fire grenade. This consisted of a glass sphere filled with CTC, that was intended to be hurled at the base of a fire (early ones used salt-water, but CTC was more effective). Carbon tetrachloride was suitable for liquid and electrical fires and the extinguishers were fitted to motor vehicles. Carbon tetrachloride extinguishers were withdrawn in the 1950s because of the chemical's toxicity – exposure to high concentrations damages the nervous system and internal organs. Additionally, when used on a fire, the heat can convert CTC to phosgene gas, formerly used as a chemical weapon.
The carbon dioxide (CO2) extinguisher was invented (at least in the US) by the Walter Kidde Company in 1924 in response to Bell Telephone's request for an electrically non-conductive chemical for extinguishing the previously difficult-to-extinguish fires in telephone switchboards. It consisted of a tall metal cylinder containing 7.5 pounds (3.4 kg) of CO2 with a wheel valve and a woven brass, cotton covered hose, with a composite funnel-like horn as a nozzle. CO2 is still popular today as it is an ozone-friendly clean agent and is used heavily in film and television production to extinguish burning stuntmen. Carbon dioxide extinguishes fire mainly by displacing oxygen. It was once thought that it worked by cooling, although this effect on most fires is negligible. An anecdotal report of a carbon dioxide fire extinguisher was published in Scientific American in 1887 which describes the case of a basement fire at a Louisville, Kentucky pharmacy which melted a lead pipe charge with CO
2 (called carbonic acid gas at the time) intended for a soda fountain which immediately extinguished the flames thus saving the building. Also in 1887, carbonic acid gas was described as a fire extinguisher for engine chemical fires at sea and ashore.
In 1928, DuGas (later bought by ANSUL) came out with a cartridge-operated dry chemical extinguisher, which used sodium bicarbonate specially treated with chemicals to render it free-flowing and moisture-resistant. It consisted of a copper cylinder with an internal CO2cartridge. The operator turned a wheel valve on top to puncture the cartridge and squeezed a lever on the valve at the end of the hose to discharge the chemical. This was the first agent available for large-scale three-dimensional liquid and pressurized gas fires, but remained largely a specialty type until the 1950s, when small dry chemical units were marketed for home use. ABC dry chemical came over from Europe in the 1950s, with Super-K being invented in the early 1960s and Purple-K being developed by the US Navy in the late 1960s. Manually applied dry agents such as graphite for class D (metal) fires had existed since WWII, but it wasn't until 1949 that Ansul introduced a pressurized extinguisher using an external CO
2 cartridge to discharge the agent. Met-L-X (sodium chloride) was the first extinguisher developed in the US, with graphite, copper, and several other types being developed later.
In the 1940s, Germany invented the liquid chlorobromomethane (CBM) for use in aircraft. It was more effective and slightly less toxic than carbon tetrachloride and was used until 1969. Methyl bromide was discovered as an extinguishing agent in the 1920s and was used extensively in Europe. It is a low-pressure gas that works by inhibiting the chain reaction of the fire and is the most toxic of the vaporizing liquids, used until the 1960s. The vapor and combustion by-products of all vaporizing liquids were highly toxic and could cause death in confined spaces.
In the 1970s, Halon 1211 came over to the United States from Europe where it had been used since the late 1940s or early 1950s. Halon 1301 had been developed by DuPont and the US Army in 1954. Both 1211 and 1301 work by inhibiting the chain reaction of the fire, and in the case of Halon 1211, cooling class A fuels as well. Halon is still in use today but is falling out of favor for many uses due to its environmental impact. Europe and Australia have severely restricted its use, since the Montreal Protocol of 1987. Less severe restrictions have been implemented in the United States, the Middle East, and Asia.
Fire extinguishers in a museum storeroom, cut to display their inner workings.
A glass grenade-style extinguisher, to be thrown into a fire.
A US copper building type soda-acid extinguisher.
A US building-type chemical foam extinguisher with contents.
Pyrene apparatus type chemical foam, 1960s
A Pyrene, brass, carbon tetrachloride extinguisher.
Pyrene 1 qt. pump-type chlorobromomethane (CB or CBM), 1960s, UK
National Methyl Bromide extinguishers, UK, 1930s–1940s.
Bell Telephone CO
2 extinguisher made by Walter Kidde, 1928.
Du Gas cartridge-operated dry chemical extinguisher, 1945.
Ansul Met-L-X cartridge-operated dry powder fire extinguisher for class D fires, 1950s.
Internationally there are several accepted classification methods for hand-held fire extinguisher. Each classification is useful in fighting fires with a particular group of fuel.
Australia and New Zealand
Specifications of fire extinguishers are set out in the standard AS/NZS 1841, the most recent version being released in 2007. All fire extinguishers must be painted signal red. Except for water extinguishers, each extinguisher has a coloured band near the top, covering at least 10% of the extinguisher's body length, specifying its contents.
|Type||Band colour||Fire classes (brackets denote sometimes applicable)|
|Dry powder (metal fires)||Lime green||D|
|Vaporizing liquid (non-halon clean agents)||Golden yellow||A||B||C||E|
|Halon||No longer produced||A||B||E|
In Australia, yellow (Halon) fire extinguishers are illegal to own or use on a fire, unless an essential use exemption has been granted, this is due to the ozone-depleting nature of halon.
According to the standard BS EN 3, fire extinguishers in the United Kingdom as all throughout Europe are red RAL 3000, and a band or circle of a second color covering between 5–10% of the surface area of the extinguisher indicates the contents. Before 1997, the entire body of the fire extinguisher was color coded according to the type of extinguishing agent.
The UK recognises six fire classes:
- Class A fires involve organic solids such as paper and wood.
- Class B fires involve flammable or combustible liquids, including petrol, grease, and oil.
- Class C fires involve flammable gases.
- Class D fires involve combustible metals.
- Class E fires involve electrical equipment/appliances.
- Class F fires involve cooking fat and oil.
Class E has been discontinued, but covered fires involving electrical appliances. This is no longer used on the basis that, when the power supply is turned off, an electrical fire can fall into any of the remaining five categories.
|Type||Old code||BS EN 3 colour code||Fire classes|
(brackets denote sometimes applicable)
|Water||Signal red||Signal red||A|
|Foam||Cream||Red with a cream panel above the operating instructions||A||B|
|Dry powder||French blue||Red with a blue panel above the operating instructions||A||B||C||E|
|Carbon dioxide, CO2||Black||Red with a black panel above the operating instructions||B||E|
|Wet chemical||Yellow (not in use)||Red with a canary yellow panel above the operating instructions||A||(B)||F|
|Class D powder||French blue||Red with a blue panel above the operating instructions||D|
|Halon 1211/BCF||Emerald green||No longer in general use||A||B||E|
In the UK, the use of Halon gas is now prohibited except under certain situations such as on aircraft and in the military and police.
Fire extinguishing performance per fire class is displayed using numbers and letters such as 13A, 55B.
EN3 does not recognise a separate electrical class - however there is an additional feature requiring special testing (35 kVdielectric test per EN 3-7:2004). A powder or CO2 extinguisher will bear an electrical pictogramme as standard signifying that it can be used on live electrical fires (given the symbol E in the table). If a water-based extinguisher has passed the 35 kV test it will also bear the same electrical pictogramme – however, any water-based extinguisher is only recommended for inadvertent use on electrical fires.
There is no official standard in the United States for the color of fire extinguishers, though they are usually red, except for class D extinguishers which are usually yellow, water and Class K wet chemical extinguishers which are usually silver, and water mist extinguishers which are usually white. Extinguishers are marked with pictograms depicting the types of fires that the extinguisher is approved to fight. In the past, extinguishers were marked with colored geometric symbols, and some extinguishers still use both symbols. The types of fires and additional standards are described in NFPA 10: Standard for Portable Fire Extinguishers, 2013 edition.
Fire extinguishing capacity is rated in accordance with ANSI/UL 711: Rating and Fire Testing of Fire Extinguishers. The ratings are described using numbers preceding the class letter, such as 1-A:10-B:C. The number preceding the A multiplied by 1.25 gives the equivalent extinguishing capability in gallons of water. The number preceding the B indicates the size of fire in square feet that an ordinary user should be able to extinguish. There is no additional rating for class C, as it only indicates that the extinguishing agent will not conduct electricity, and an extinguisher will never have a rating of just C.
|Class A||Class A||Class A||Class A||Ordinary combustibles|
|Class B||Class B||Class B||Class B||Flammable liquids|
|Class C||Class C||Class C||Flammable gases|
|Class C||Unclassified||Unclassified||Class E||Electrical equipment|
|Class D||Class D||Class D||Class D||Combustible metals|
|Class K||Class F||Class F||Class F||Cooking oil or fat|
Fire extinguishers are usually fitted in buildings at an easily accessible location, such as against a wall in a high-traffic area. They are also often fitted to motor vehicles, watercraft, and aircraft - this is required by law in many jurisdictions, for identified classes of vehicles. Under NFPA 10 all commercial vehicles must carry at least one fire extinguisher, with size/UL rating depending on type of vehicle and cargo (i.e., fuel tankers usually must have a 20 lb (9.1 kg), while most others can carry a 5 lb (2.3 kg)). The revised NFPA 10 created criteria on the placement of "fast flow extinguishers" in locations such as those storing and transporting pressurized flammable liquids and pressurized flammable gas or areas with possibility of three-dimensional class B hazards are required to have "fast flow extinguishers" as required by NFPA 22.214.171.124. Varying classes of competition vehicles require fire extinguishing systems, the simplest requirements being a 1A:10BC hand-held portable extinguisher mounted to the interior of the vehicle.
The height limit for installation, as determined by the National Fire Protection Association (NFPA), is 60 in (1.5 m) for fire extinguishers weighing less than 40 lb (18 kg). However, compliance with the Americans with Disabilities Act (ADA) also needs to be followed within the United States. The ADA height limit of the fire extinguisher, as measured at the handle, is 48 in (1.2 m). Fire extinguisher installations are also limited to protruding no more than 4 inches into the adjacent path of travel. The ADA rule states that any object adjacent to a path of travel may not project more than 4 in (10 cm) if the object's bottom leading edge is higher than 27 in (0.69 m). The 4-inch protrusion rule was designed to protect people with low-vision and those who are blind. The height limit rule of 48 inches is primarily related to access by people with wheelchairs but it is also related to other disabilities as well. Prior to 2012, the height limit was 54 in (1.4 m) for side-reach by wheelchair-accessible installations. Installations made prior to 2012 at the 54-inch height are not required to be changed.
In New Zealand, the mandatory installation of fire extinguishers in vehicles is limited to self-propelled plant in agriculture and arboriculture, passenger service vehicles with more than 12 seats and vehicles that carry flammable goods.NZ Transport Agency recommends that all company vehicles carry a fire extinguisher, including passenger cars.
Fire extinguishers mounted inside aircraft engines are called extinguishing bottles or fire bottles.
Types of extinguishing agents
This is a powder-based agent that extinguishes by separating the four parts of the fire triangle. It prevents the chemical reactions involving heat, fuel, and oxygen, thus extinguishing the fire. During combustion, the fuel breaks down into free radicals, which are highly reactive fragments of molecules that react with oxygen. The substances in dry chemical extinguishers can stop this process.
- Monoammonium phosphate, also known as tri-class, multipurpose, or ABC dry chemical, used on class A, B and C fires. It receives its class A rating from the agent's ability to melt and flow at 177 °C (351 °F) to smother the fire. More corrosive than other dry chemical agents. Pale yellow in color.
- Sodium bicarbonate, regular or ordinary used on class B and C fires, was the first of the dry chemical agents developed. In the heat of a fire, it releases a cloud of carbon dioxide that smothers the fire. That is, the gas drives oxygen away from the fire, thus stopping the chemical reaction. This agent is not generally effective on class A fires because the agent is expended and the cloud of gas dissipates quickly, and if the fuel is still sufficiently hot, the fire starts up again. While liquid and gas fires do not usually store much heat in their fuel source, solid fires do. Sodium bicarbonate was very common in commercial kitchens before the advent of wet chemical agents, but now is falling out of favor as it is much less effective than wet chemical agents for class K fires, less effective than Purple-K for class B fires, and is ineffective on class A fires. White or blue in color.
- Potassium bicarbonate (principal constituent of Purple-K), used on class B and C fires. About two times as effective on class B fires as sodium bicarbonate, it is the preferred dry chemical agent of the oil and gas industry. The only dry chemical agent certified for use in ARFF by the NFPA. Colored violet to distinguish it.
- Potassium bicarbonate & Urea Complex (AKA Monnex), used on class B and C fires. More effective than all other powders due to its ability to decrepitate (where the powder breaks up into smaller particles) in the flame zone creating a larger surface area for free radical inhibition. Grey in color.
- Potassium chloride, or Super-K, dry chemical was developed in an effort to create a high efficiency, protein-foam compatible dry chemical. Developed in the 1960s, prior to Purple-K, it was never as popular as other agents since, being a salt, it was quite corrosive. For B and C fires, white in color.
- Foam-compatible, which is a sodium bicarbonate (BC) based dry chemical, was developed for use with protein foams for fighting class B fires. Most dry chemicals contain metal stearates to waterproof them, but these will tend to destroy the foam blanket created by protein (animal) based foams. Foam compatible type uses silicone as a waterproofing agent, which does not harm foam. Effectiveness is identical to regular dry chemical, and it is light green in color (some ANSUL brand formulations are blue). This agent is generally no longer used since most modern dry chemicals are considered compatible with synthetic foams such as AFFF.
- MET-L-KYL / PYROKYL is a specialty variation of sodium bicarbonate for fighting pyrophoric (ignites on contact with air) liquid fires. In addition to sodium bicarbonate, it also contains silica gel particles. The sodium bicarbonate interrupts the chain reaction of the fuel and the silica soaks up any unburned fuel, preventing contact with air. It is effective on other class B fuels as well. Blue/red in color.
A typical dry chemical extinguisher containing 5 lb (2.3 kg). of monoammonium phosphate dry chemical.
A 10 lb (4.5 kg) stored pressure purple-K fire extinguisher
An 18 lb (8.2 kg) US Navy cartridge-operated purple-K dry chemical (potassium bicarbonate) extinguisher.
Met-L-Kyl cartridge-operated fire extinguisher for pyrophoric liquid fires.
Applied to fuel fires as either an aspirated (mixed and expanded with air in a branch pipe) or nonaspirated form to create a frothy blanket or seal over the fuel, preventing oxygen reaching it. Unlike powder, foam can be used to progressively extinguish fires without flashback.
- Aqueous film-forming foam (AFFF), used on A and B fires and for vapor suppression. The most common type in portable foam extinguishers. AFFF was developed in the 1960s under Project Light Water in a joint venture between 3M and the U.S. Navy. AFFF forms a film that floats out before the foam blanket, sealing the surface and smothering the fire by excluding oxygen. AFFF is widely used for ARFF firefighting at airports, often in conjunction with purple-K dry chemical. It contains fluoro-tensides which can be accumulated in the human body. The long-term effects of this on the human body and environment are unclear at this time. AFFF can be discharged through an air-aspirating branchpipe nozzle or a spray nozzle and is now produced only in pre-mix form, where the foam concentrate is stored mixed with water. In the past, as solid charge model was produced, the AFFF concentrate was housed as a dry compound in an external, disposable cartridge in a specially designed nozzle. The extinguisher body was charged with plain water, and the discharge pressure mixed the foam concentrate with the water upon squeezing the lever. These extinguishers received double the rating of a pre-mix model (40-B instead of 20-B), but are now considered obsolete, as parts and refill cartridges have been discontinued by the manufacturer.
- Alcohol-resistant aqueous film-forming foams (AR-AFFF), used on fuel fires containing alcohol. Forms a membrane between the fuel and the foam preventing the alcohol from breaking down the foam blanket.
- Film-forming fluoroprotein (FFFP) contains naturally occurring proteins from animal by-products and synthetic film-forming agents to create a foam blanket that is more heat resistant than the strictly synthetic AFFF foams. FFFP works well on alcohol-based liquids and is used widely in motorsports. As of 2016, Amerex has discontinued production of FFFP, instead using AR-AFFF made by Solberg. Existing model 252 FFFP units can maintain their UL listing by using the new charge, but only the model 250 will be produced in the future.
- Compressed air foam system (CAFS): The CAFS extinguisher (example: TRI-MAX Mini-CAF) differs from a standard stored-pressure premix foam extinguisher in that it operates at a higher pressure of 140 psi, aerates the foam with an attached compressed gas cylinder instead of an air-aspirating nozzle, and uses a drier foam solution with a higher concentrate-to-water ratio. Generally used to extend a water supply in wildland operations. Used on class A fires and with very dry foam on class B for vapor suppression. These are very expensive, special purpose extinguishers typically used by fire departments or other safety professionals.
- Arctic Fire is a liquid fire extinguishing agent that emulsifies and cools heated materials more quickly than water or ordinary foam. It is used extensively in the steel industry. Effective on classes A, B, and D.
- FireAde is a foaming agent that emulsifies burning liquids and renders them non-flammable. It is able to cool heated material and surfaces similar to CAFS. Used on A and B (said to be effective on some class D hazards, although not recommended due to the fact that fireade still contains amounts of water which will react with some metal fires).
- Cold Fire is an organic, eco-friendly wetting agent that works by cooling, and by encapsulating the hydrocarbon fuel, which prevents it from entering into the combustion reaction. Bulk Cold Fire is used in booster tanks and is acceptable for use in CAFS systems. Cold Fire is UL listed for A and B fires only. Aerosol versions are preferred by users for cars, boats, RVs, and kitchens. Used primarily by law enforcement, fire departments, EMS, and the racing industry across North America. Cold Fire offers Amerex equipment (converted 252 and 254 models) as well as imported equipment in smaller sizes.
1970s Light Water AFFF foam fire extinguisher
Amerex Solid-Charge AFFF Fire Extinguisher, 1980s (obsolete)
A 2.5 US gal (9.5 l) USCG-approved 2+1⁄2-gallon AFFF foam fire extinguisher
Water cools burning material and is very effective against fires in furniture, fabrics, etc. (including deep-seated fires). Water-based extinguishers cannot be used safely on energized electrical fires or flammable liquid fires.
- Pump-Type water consists of a 9.5-litre (2+1⁄2 US gal) or 19-litre (5 US gal) non-pressurized metal or plastic container with a pump mounted to it, as well as a discharge hose and nozzle. Pump type water extinguishers are often used where freezing conditions may occur, as they can be economically freeze-protected with calcium chloride (except stainless steel models), such as barns, outbuildings and unheated warehouses. They are also useful where many, frequent spot fires may occur, such as during fire watch for hot work operations. They are dependent on the user's strength to produce a decent discharge stream for firefighting. Water and antifreeze are the most common, but loaded stream and foam designs were made in the past. Backpack models exist for wildland firefighting and may be solid material such as metal or fiberglass, or collapsible vinyl or rubber bags for ease of storage.
- Air-pressurized water (APW) cools burning material by absorbing heat from burning material. Effective on class A fires, it has the advantage of being inexpensive, harmless, and relatively easy to clean up. In the United States, APW units contain 9.5 litres (2+1⁄2 US gal) of water in a tall, stainless steel cylinder. In Europe, they are typically mild steel, lined with polyethylene, painted red and contain 6–9 l (1.6–2.4 US gal) of water.
- Water mist (WM) uses a fine misting nozzle to break up a stream of de-ionized (distilled) water to the point of not conducting electricity back to the operator. Class A and C rated. It is used widely in hospitals and MRI facilities because it is both completely non-toxic and does not cause cardiac sensitization like some gaseous clean agents. These extinguishers come in 6.6-litre (1+3⁄4 US gal) and 9.5-litre (2+1⁄2 US gal) sizes, painted white in the United States. Models used in MRI facilities are non-magnetic and are safe for use inside the room that the MRI machine is operating. Models available in Europe come in smaller sizes as well, and some even carry a Class F rating for commercial kitchens, essentially using steam to smother the fire and the water content to cool the oil.
General 2.5 gal. pump-type water fire extinguisher, 1960s, US
Stored pressure water extinguisher
Stored pressure loaded stream fire extinguisher
2.5 gallon water mist fire extinguisher for medical and MRI facilities
6-liter wet chemical fire extinguisher for use in commercial kitchens
Indian 5-gal. backpack pump tank for wildland firefighting, US
Wet chemical and water additives
Wet chemical (potassium acetate, potassium carbonate, or potassium citrate) extinguishes the fire by forming an air-excluding soapy foam blanket over the burning oil through the chemical process of saponification (a base reacting with a fat to form a soap) and by the water content cooling the oil below its ignition temperature. Generally, class A and K (F in Europe) only, although older models also achieved class B and C fire-fighting capability in the past, current models are rated A:K (Amerex, Ansul, Buckeye and Strike First) or K only (Badger/Kidde).
- Wetting agents: Detergent based additives used to break the surface tension of water and improve penetration of class A fires.
- Antifreeze chemicals added to water to lower its freezing point to about −40 °C (−40 °F). Has no appreciable effect on extinguishing performance. Can be glycol based or loaded stream, see below.
- Loaded Stream: An alkali metal salt solution added to water to lower its freezing point to about −40 °C (−40 °F). Loaded stream is basically concentrated wet chemical, discharged through a straight stream nozzle, intended for class A fires. In addition to lowering the freezing point of the water, loaded stream also increases penetration into dense class A materials and will give a slight class B rating (rated 1-B in the past), though current[when?] loaded stream extinguishers are rated only 2-A. Loaded Stream is very corrosive; extinguishers containing this agent must be recharged annually to check for corrosion.
Halons, Halon-replacement clean agents and carbon dioxide
Clean agents extinguish fire by displacing oxygen (CO2 or inert gases), removing heat from the combustion zone (Halotron-1, FE-36, Novec 1230) or inhibiting the chemical chain reaction (Halons). They are referred to as clean agents because they do not leave any residue after discharge, which is ideal for protecting sensitive electronics, aircraft, armored vehicles and archival storage, museums, and valuable documents.
- Halon (including Halon 1211 and Halon 1301), are gaseous agents that inhibit the chemical reaction of the fire. Classes B:C for 1301 and smaller 1211 fire extinguishers (2.3 kg; under 9 lbs) and A:B:C for larger units (9–17 lb or 4.1–7.7 kg). Halon gases are banned from new production under the Montreal Protocol, as of January 1, 1994 as its properties contribute to ozone depletion and long atmospheric lifetime, usually 400 years. Halon may be recycled and used to fill newly manufactured cylinders, however, only Amerex continues to do this. The rest of the industry has moved to halon alternatives, nevertheless, halon 1211 is still vital to certain military and industrial users, so there is a need for it.
Halon was completely banned in Europe and Australia except for critical users like law enforcement and aviation, resulting in stockpiles either being destroyed via high heat incineration or being sent to the United States for reuse. Halon 1301 and 1211 are being replaced with new halocarbon agents which have no ozone depletion properties and low atmospheric lifetimes, but are less effective. Halon 2402 is a liquid agent (dibromotetrafluoroethane) which has had limited use in the West due to its higher toxicity than 1211 or 1301. It is widely used in Russia and parts of Asia, and it was used by Kidde's Italian branch, marketed under the name "Fluobrene".
- Halocarbon replacements, HCFC Blend B (Halotron I, American Pacific Corporation), HFC-227ea (FM-200, Great Lakes Chemicals Corporation), and HFC-236fa (FE-36, DuPont), have been approved by the FAA for use in aircraft cabins in 2010. Considerations for halon replacement include human toxicity when used in confined spaces, ozone depleting potential, and greenhouse warming potential. The three recommended agents meet minimum performance standards, but uptake has been slow because of disadvantages. Specifically, they require two to three times the concentration to extinguish a fire compared with Halon 1211. They are heavier than halon, require a larger bottle because they are less effective, and have greenhouse gas potential. Research continues to find better alternatives.
- CO2, a clean gaseous agent which displaces oxygen. Highest rating for 20 lb (9.1 kg) portable CO2 extinguishers is 10B:C. Not intended for class A fires, as the high-pressure cloud of gas can scatter burning materials. CO2 is not suitable for use on fires containing their own oxygen source, metals or cooking media, and may cause frostbite and suffocation if used on human beings.
- Novec 1230 fluid (AKA dry water, or Saffire fluid), a fluorinated ketone that works by removing massive amounts of heat. Available in fixed systems and wheeled units in the US and in portables in Australia. Unlike other clean agents, this one has the advantage of being a liquid at atmospheric pressure and can be discharged as a stream or a rapidly vaporizing mist, depending on application.
- Potassium aerosol particle-generator, contains a form of solid potassium salts and other chemicals referred to as aerosol-forming compounds (AFC). The AFC is activated by an electric current or other thermodynamic exchange which causes the AFC to ignite. The majority of installed currently are fixed units due to the possibility of harm to the user from the heat generated by the AFC generator.
- E-36 Cryotec, a type of high concentration, high-pressure wet chemical (potassium acetate and water), it is being used by the U.S. Military in applications like the Abrams tank to replace the aging halon 1301 units previously installed.
Amerex 10lb. CO
2 Fire Extinguisher, Circa 1989, US
Halon 1211 Fire Extinguisher
Halon 1301 Fire Extinguisher
5lb. Halotron-1 fire extinguisher
FE-36 Cleanguard fire extinguisher
Class D dry powder and other agents for metal fires
There are several class D fire extinguisher agents available; some will handle multiple types of metals, others will not.
- Sodium chloride (Super-D, Met-L-X, M28, Pyrene Pyromet*) contains sodium chloride salt, which melts to form an oxygen-excluding crust over the metal. A thermoplastic additive such as nylon is added to allow the salt to more readily form a cohesive crust over the burning metal. Useful on most alkali metals including sodium and potassium, and other metals including magnesium, titanium, aluminum, and zirconium.
- Copper-based (Copper Powder Navy 125S) developed by the U.S. Navy in the 1970s for hard-to-control lithium and lithium-alloy fires. The powder smothers and acts as a heat sink to dissipate heat, but also forms a copper-lithium alloy on the surface which is non-combustible and cuts off the oxygen supply. Will cling to a vertical surface. Lithium only.
- Graphite-based (G-Plus, G-1, Lith-X, Chubb Pyromet) contains dry graphite that smothers burning metals. The first type developed, designed for magnesium, works on other metals as well. Unlike sodium chloride powder extinguishers, the graphite powder fire extinguishers can be used on very hot burning metal fires such as lithium, but unlike copper powder extinguishers will not stick to and extinguish flowing or vertical lithium fires. Like copper extinguishers, the graphite powder acts as a heat sink as well as smothering the metal fire.
- Sodium carbonate-based (Na-X) is used where stainless steel piping and equipment could be damaged by sodium chloride-based agents to control sodium, potassium, and sodium-potassium alloy fires. Limited use on other metals. Smothers and forms a crust.
- Ternary eutectic chloride (T.E.C.) dry powder is a dry powder invented in 1959 by Lawrence H Cope, a research metallurgist working for the UK Atomic Energy Authority, and licensed to John Kerr Co. of England. It consists of a mixture of three powdered salts: sodium, potassium and barium chloride. T.E.C. forms an oxygen-excluding layer of molten salt on the metal's surface. Along with Met-L-X (sodium chloride), T.E.C has been reported to be one of the most effective agents for use on sodium, potassium, and NaK fires, and is used specifically on atomic metals like uranium and plutonium as it will not contaminate the valuable metal unlike other agents. T.E.C. is quite toxic, due to the barium chloride content, and for this reason is no longer used in the UK, and was never used in the US aside from radioactive material handling glove boxes, where its toxicity was not an issue due their confined nature. T.E.C. is still widely used in India, despite toxicity, while the West uses chiefly sodium chloride, graphite, and copper types of powder and considers T.E.C. obsolete.
- Trimethoxyboroxine (TMB) liquid is a boron compound dissolved in methanol to give it proper fluidity and allow it to be discharged from a portable fire extinguisher. It was developed in the late 1950s by the U.S. Navy for use on magnesium fires, especially crashed aircraft and aircraft wheel fires from hard landings. It is unique as an extinguishing agent in that the agent itself is a flammable liquid. When TMB contacts the fire, the methanol ignites and burns with a greenish flame due to the boron. As the methanol burns off, a glassy coating of boric oxide is left on the surface of the metal, creating an air-excluding crust. These extinguishers were made by the Ansul Chemical Co. utilizing TMB agent manufactured by the Callery Chemical Company, and were modified 2.5-gallon water extinguishers (Ansul used re-branded Elkhart extinguishers at the time), with a variable-stream nozzle that could deliver a straight stream or spray at the squeeze of a lever. A 6-inch fluorescent orange band with the letters "TMB" stenciled in black identified TMB from other extinguishers. This agent was problematic in that it had a shelf life of only six months to a year once the extinguisher was filled, since the methanol is extremely hygroscopic (absorbs moisture from the air), which causes corrosion to the extinguisher and renders its use on fire dangerous. These extinguishers were used from the 1950s–1970s in various applications, such as the MB-1 and MB-5 crash trucks.
TMB was used experimentally by the US Air Force, specifically with regard to B-52 engine assemblies, and was tested in modified 10-gallon wheeled CBM extinguishers. Other agents were added to suppress the methanol flare up, such as chlorobromomethane (CBM), Halon 2402, and Halon 1211, with varied success. Halon 1211 was the most successful, and the combined TMB pressurized with halon 1211 and nitrogen was called Boralon was used experimentally by the Los Alamos National Laboratory for use on atomic metals, using sealed cylinder extinguishers made by Metalcraft and Graviner which eliminated the moisture contamination problem. TMB/Boralon was abandoned in favor of more versatile agents, though it is still mentioned in most US firefighting literature.
- Buffalo M-X liquid was a short-lived oil-based extinguishing agent for magnesium fires, made by Buffalo in the 1950s. It was discovered by the Germans in WWII that a heavy oil could be applied to burning magnesium chips to cool and smother them, and was easy to apply from a pressurized extinguisher, which was made by the German firm Total. After the war, the technology was more generally disseminated.
Buffalo marketed a 2.5-gallon and 1-quart extinguisher using M-X liquid discharged through a low-velocity shower head-type nozzle, but it was met with limited success, as it was going up against Ansul's Met-L-X, which could be used on more types of metals and was non-combustible. M-X had the advantage of being easy to recharge and non-corrosive since it was oil-based, but production did not last long due to its limited applications.
- Some water-based suppressants may be used on certain class D fires, such as burning titanium and magnesium. Examples include the Fire Blockade and FireAde brands of suppressant. Some metals, such as elemental lithium, will react explosively with water so water-based chemicals are not used on such fires.
Most class D extinguishers will have a special low-velocity nozzle or discharge wand to gently apply the agent in large volumes to avoid disrupting any finely divided burning materials. Agents are also available in bulk and can be applied with a scoop or shovel.
- Note. "Pyromet" is a trade name that refers to two separate agents. Invented by Pyrene Co. Ltd. (UK) in the 1960s, it was originally a sodium chloride formulation with monoammonium phosphate, protein, clay and waterproofing agents. Modern Pyromet made by Chubb Fire is a graphite formulation.
Ansul Met-L-X 30lb. cartridge-operated sodium chloride dry powder
Amerex 30lb. Stored Pressure Sodium Chloride Class D Dry Powder, 1990s, US
Ansul Lith-X Cartridge-Operated Fire Extinguisher, graphite-base for lithium fires and other alkali metals
Ansul 30lb. Na-X cartridge-operated sodium carbonate fire extinguisher for sodium fires using non-corrosive agent.
A TMB extinguisher for magnesium fires
Buffalo fire extinguishers for magnesium fires using M-X liquid
Ternary Eutectic Chloride fire extinguisher for metal fires, UK.
Fire extinguishing ball
Several modern "ball" or grenade-style extinguishers are available on the market. The modern version of the ball is a hard foam shell, wrapped in fuses that lead to a small black powder charge within. The ball bursts shortly after contact with flame, dispersing a cloud of ABC dry chemical powder which extinguishes the fire. The coverage area is about 5 m2 (54 sq ft). One benefit of this type is that it may be used for passive suppression. The ball can be placed in a fire-prone area and will deploy automatically if a fire develops, being triggered by heat. They may also be manually operated by rolling or tossing into a fire. Most modern extinguishers of this type are designed to make a loud noise upon deployment.
This technology is not new, however. In the 1800s, glass fire grenades filled with suppressant liquids were popular. These glass fire grenade bottles are sought by collectors. Some later brands, such as Red Comet, were designed for passive operation and included a special holder with a spring-loaded trigger that would break the glass ball when a fusible link melted. As was typical of this era, some glass extinguishers contained the toxic carbon tetrachloride.
Condensed aerosol fire suppression
Condensed aerosol fire suppression is a particle-based form of fire extinction similar to gaseous fire suppression or dry chemical fire extinction. As with gaseous fire suppressants, condensed aerosol suppressants use clean agents to suppress the fire. The agent can be delivered by means of mechanical operation, electric operation, or combined electro-mechanical operation. To the difference of gaseous suppressants, which emit only gas, and dry chemical extinguishers, which release powder-like particles of a large size (25–150 µm) condensed aerosols are defined by the National Fire Protection Association as releasing finely divided solid particles (generally <10 µm), usually in addition to gas.
Whereas dry chemical systems must be directly aimed at the flame, condensed aerosols are flooding agents and therefore effective regardless of the location and height of the fire. Wet chemical systems, such as the kind generally found in foam extinguishers, must, similarly to dry chemical systems, be sprayed directionally, onto the fire. Additionally, wet chemicals (such as potassium carbonate) are dissolved in water, whereas the agents used in condensed aerosols are microscopic solids.
In 2015, researchers from George Mason University announced that high volume sound with low bass frequencies in the 30 to 60 hertz range drives oxygen away from the combustion surface, extinguishing the fire, a principle was previously tested by the Defense Advanced Research Projects Agency (DARPA). One proposed application is to extinguish fires in outer space, with none of the clean-up required for mass-based systems.
Another proposed solution for fire extinguishers in space is a vacuum cleaner that extracts the combustible materials.
Most countries in the world require regular fire extinguisher maintenance by a competent person to operate safely and effectively, as part of fire safety legislation. Lack of maintenance can lead to an extinguisher not discharging when required, or rupturing when pressurized. Deaths have occurred, even in recent times, from corroded extinguishers exploding.
In the United States, state and local fire codes, as well as those established by federal agencies such as the Occupational Safety and Health Administration, are generally consistent with standards established by the National Fire Protection Association (NFPA). They commonly require, for fire extinguishers in all buildings other than single-family dwellings, inspections every 30 days to ensure the unit is pressurized and unobstructed (done by an employee of the facility) and an annual inspection and service by a qualified technician. Some jurisdictions require more frequent service. The servicer places a tag on the extinguisher to indicate the type of service performed (annual inspection, recharge, new fire extinguisher). Hydrostatic pressure testing for all types of extinguishers is also required, generally every five years for water and CO2 models up to every 12 years for dry chemical models.
Recently the NFPA and ICC voted to allow for the elimination of the 30-day inspection requirement so long as the fire extinguisher is monitored electronically. According to NFPA, the system must provide record keeping in the form of an electronic event log at the control panel. The system must also constantly monitor an extinguisher's physical presence, internal pressure and whether an obstruction exists that could prevent ready access. In the event that any of the above conditions are found, the system must send an alert to officials so they can immediately rectify the situation. Electronic monitoring can be wired or wireless.
In the UK, three types of maintenance are required:
- Basic service: All types of extinguisher require a basic inspection annually to check weight, externally validate the correct pressure, and find any signs of damage or corrosion. Cartridge extinguishers are to be opened up for internal inspection, and to have the weight of the cartridge tested. Labels must be inspected for legibility, and where possible, dip tubes, hoses and mechanisms must be tested for clear, free operation.
- Extended service: Water, wet chemical, foam, and powder extinguishers require a more detailed examination every five years, including a test discharge and recharge. On stored pressure extinguishers, this is the only opportunity to internally inspect for damage/corrosion.
- Overhaul: CO2 extinguishers, due to their high operating pressure, are subject to pressure vessel safety legislation, and must be hydraulic pressure tested, inspected internally and externally, and date stamped every 10 years. As it cannot be pressure tested, a new valve is also fitted. If any part of the extinguisher is replaced with a part from another manufacturer, then the extinguisher will lose its fire rating.
In the United States, there are 3 types of service:
- Maintenance inspection 
- Internal maintenance:
- Water – annually (some states) or 5 years (NFPA 10, 2010 edition)
- Foam – every 3 years
- Wet chemical, and CO
2 – every 5 years
- Dry chemical and dry powder – every 6 years
- Halon and clean agents – every 6 years.
- Cartridge-operated dry chemical or dry powder – annually
- Stored-pressure dry chemical mounted on vehicles – annually
- Hydrostatic testing
Vandalism and extinguisher protection
Fire extinguishers are sometimes a target of vandalism in schools and other open spaces. Extinguishers are occasionally partially or fully discharged by a vandal, impairing the extinguisher's actual fire-fighting abilities.
In open public spaces, extinguishers are ideally kept inside cabinets that have glass that must be broken to access the extinguisher, or which emit an alarm siren that cannot be shut off without a key, to alert people the extinguisher has been handled by an unauthorized person if a fire is not present. This also alerts maintenance to check an extinguisher for usage so that it may be replaced if it has been used.
- ^"Fire extinguishers: The unlikely origin story". Fire Rescue 1. 21 November 2016. Retrieved 8 March 2021.
- ^"Miscellanea". Manchester Mercury. 26 March 1816. p. 3.
- ^U.S. Patent 233,235
- ^U.S. Patent 258,293
- ^"Staffordshire Past Track – "Petrolex" half gallon fire extinguisher". Archived from the original on 2010-01-22. Retrieved 2009-05-25.
- ^Loran and the fire extinguisherArchived 2011-07-27 at the Wayback Machine at p-lab.org (in Russian)
- ^U.S. Patent 1,010,870, filed April 5, 1910.
- ^U.S. Patent 1,105,263, filed Jan 7, 1911.
- ^"Pyrene Fire Extinguishers". Vintage Fire Extinguishers. Archived from the original on 25 March 2010. Retrieved 23 December 2009.
- ^"Carbon Tetrachloride Health and Safety Guide". IPCS International Programme on Chemical Safety. Retrieved 25 December 2009.
- ^U.S. Patent 1,760,274, filed Sept 26, 1925.
- ^McCarthy, Robert E (1992-06-18). Secrets of Hollywood special effects. ISBN . Retrieved 2010-03-17 – via Google Books.
- ^Scientific American. Munn & Company. 1887-09-03. p. 149.
- ^Scientific American, "Improved Fire Extinguishing Apparatus For Vessels". Munn & Company. 1877-06-23. pp. 383, 388.
- ^U.S. Patent 1,792,826
- ^U.S. Patent 1,793,420
- ^"Questions and Answers on Halons and Their Substitutes". §B.11. Archived from the original on 2015-09-24. Retrieved 19 November 2016.
- ^"Halon Disposal". Ozone Protection. Australian Government Department of the Environment and Heritage (Australia). Archived from the original on 2006-09-16. Retrieved 2006-12-12.
- ^"ExtinguisherServicing – Everything you need to know". Retrieved 19 November 2016.
- ^"Fire Extinguishers – Classes, Colour Coding, Rating, Location and Maintenance : Firesafe.org.uk". www.firesafe.org.uk.
- ^"Disposal Of Halon – Envirowise". Archived from the original on 2008-12-03. Retrieved 2007-09-22.
- ^"Do you need to carry a fire extinguisher in a company vehicle?". August 27, 2018.
- ^"Your safe driving policy"(PDF).
- ^https://www.skybrary.aero/index.php/Aircraft_Fire_Extinguishing_Systems Aircraft Fire Extinguishing Systems
- ^"Wasserfilmbildendes Schaummittel – Extensid AFFF". 071027 intersales.info
- ^"Handheld Fire Extinguishers". Retrieved 2012-04-09.
- ^"Options to the Use of Halons for Aircraft Fire Suppression Systems – 2012 Update"(PDF). p. 11. Retrieved 2012-04-09.
- ^"Options to the Use of Halons for Aircraft Fire Suppression Systems – 2012 Update"(PDF). p. xvii. Retrieved 2012-04-09.
- ^U.S. Patent 3,095,372, filed July 5, 1960. UK Patent GB884946.
- ^"The Non Numismatic Bibliography of Dr L.H. Cope". Retrieved 19 November 2016.
- ^Extinguishment of Alkali Metal Fires, S.J. Rodgers and W.A. Everson, Technical Documentary Report APL-TDR 64-114, Air Force Laboratory, Wright-Patterson Air Force Base, Ohio, 1964, pp. 28–31.
- ^Fire Protection Handbook, Thirteenth Edition, National Fire Protection Association, Boston, 1969, Ch. 15, p. 54
- ^Personnel, United States Bureau of Naval (1 January 1959). "Aviation Boatswain's Mate 1 & C: Navy Training Courses". U.S. Government Printing Office. Retrieved 19 November 2016 – via Google Books.
- ^JIOA Final Report 41. "German Chemical Fire Extinguishers", Joint Intelligence Objectives Agency, Smith, Carlisle F, Washington DC, October 1945.
- ^"Fireade 2000 Applications". Archived from the original on 2009-11-01. Retrieved 2009-11-10.
- ^"Archived copy". Archived from the original on 2017-02-20. Retrieved 2017-02-19.CS1 maint: archived copy as title (link)
- ^Chuck a ball to put out fire. Earth Times. 14 September 2007.
- ^"firegrenade.com". firegrenade.com. 2007-08-23. Retrieved 2012-08-04.
- ^National Fire Protection AssociationArchived 2012-04-01 at the Wayback Machine, "Report on Aerosol Extinguishing Technology,".
- ^"Dousing flames with low-frequency sound waves". Physics World. 2 April 2015.
- ^Conrad, Henry (March 25, 2015). "Two students created a device that extinguishes fires with soundwaves". ZME Science. Retrieved March 25, 2015.
- ^Nakumura, Yuji. "Novel Fire Extinguisher Method Using Vacuuming Force Applicable to Space Habitats". Fire Technology. doi:10.1007/s10694-019-00854-4.
- ^Charpentier, Will. "NFPA Regulations on Fire Extinguishers". HomeSteady. Leaf Group. Retrieved 23 June 2018.
- ^"Common Myth #33"(PDF). 1 March 2013.
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