A Stitch in Time Saves Nine

Miners are adopting first-response firefighting training and equipment and suppliers are eager to support the trend

By Jesse Morton, Technical Writer

A longtime Drägerman told Coal Age companies and miners are increasingly adopting first-response firefighting equipment, processes and training. “It is definitely getting some traction in the industry,” said Kent Armstrong, global business development manager, mining. “Now more people are looking at this as a possible solution, a better solution for first-response underground,” he said. “MSHA has also supported first-response more and more. That is critical.”

Companies seeking to adopt and deploy are hoping to empower employees with critical safety skills and the ability to prevent a minor fire from becoming a major one that interrupts operations.

“If you can put that fire out quickly with the right tools it can be very beneficial to operations,” Armstrong said. “Municipal firefighting authorities will tell you that if you can get there and get a hose on a fire within the first 15 or 20 minutes, you’ve got a chance. You wait any length of time and, well, coal burns,” he said. “Many companies reflect on the fact that with the right equipment, service and support, the right tools and training, it could be a good advantage in the long run.”

WVU Training Uses Dräger SCBA

In March, a team from CONSOL Energy made headlines for training in first-response firefighting at the Harvey Mine BMX Portal in West Finley, West Virginia (WV), according to The Intelligencer (Wheeling, WV). The training and the facility is administered by the West Virginia University (WVU) Mining Extension.

As part of the training, the team worked with local first responders to battle a staged diesel fire. The fictional scenario that provided the context of the blaze included a severe burn victim and 170 people trapped 500 ft underground.

The team was one of the growing number of first-responder brigades at CONSOL Energy. The WVU extension was the preferred supplier for the training because it specializes in first-response firefighting in coal applications and in underground metal/nonmetal applications, Armstrong said. The courses are offered “using different types of breathing apparatuses and equipment, bunker gear and equipment, from a first-response standpoint.”

That equipment includes the Dräger SCBA (self-contained breathing apparatus) and the training programs include technical support from Dräger. “We’ve been doing this for quite some time with WVU,” he said.

The Dräger SCBA for mining applications is similar in design, function and performance to that made by the supplier for use in municipal first-response firefighting applications. In contrast to the supplier’s renowned rebreathers, the SCBA is stored underground along with spare cylinders of fresh air.

“When you use one cylinder you come back to fresh air. You rest, change out cylinders and go back in,” Armstrong said. Compared to rebreathers and competitor solutions, the Dräger “SCBA is easier to train on; easier to store, service and maintain,” he said. “For first-response underground, the SCBA has been the apparatus of choice for that reason.”

First-response firefighting procedures, training and equipment will give CONSOL Energy “the first stop-gap so that mine rescue can get there and get underground and support the fire team,” Armstrong said. “They are underground. They are ready to do it. They can respond quickly, efficiently,” he said. “This is what their company goals are, giving the miners the tools to do the job safely.”

Foam Limits No-Go Zone Size

Weber Mining & Tunneling said the Rocsil Foam injection system for the remote sealing of shafts, drifts and portals can help a coal miner cut costs, increase uptime and improve safety.

“This innovative approach is particularly significant as it sets a new industry benchmark with Rocsil Foam seals capable of delivering overpressure remote seals,” said Anthony Ferrenbach, general manager, the Americas. The approach represents “a leap forward in our ability to protect mines and their workers from the devastating impacts of underground fires and heating events.”

The foam is an “expansive resin engineered specifically for the coal mining sector to address the unique challenges of controlling fires in an underground environment,” he said. Company literature said it is a “high-expanding, two-component foam designed for rapid filling of large voids and cavities.” Large can mean up to or greater than 150 m³. “These foams have a very good resistance to fire and fulfill the standards in all countries for a use as cavity filler in underground coal mines.”

The foam is ideal for “when access to the fire zone is restricted due to safety concerns, blocked passages, or a lack of firefighting resources,” Ferrenbach said. “Rocsil Foam provides an indirect, yet highly effective, means of fire suppression,” he said. “It is injected from the surface and expands to fill up to the mine’s roof and ribs, creating an airtight barrier.”

The barrier serves as a temporary seal that can cut off oxygen to a blaze or heat event. The seals “serve as ventilation control structures, aimed at isolating the fire-affected area,” Ferrenbach said. “These seals can be established either directly within the mine or remotely via boreholes.”

Typically, the process uses a minimum of two boreholes. Through one, a camera is suspended to monitor progress. The camera supports remote control of the process. Through the other borehole, the foam is piped into the drift, shaft, portal or cavity.

The remotely controlled injection system uses “specially designed equipment to efficiently administer the foam into mine roadways or shafts, eliminating the need for labor to be physically present underground or in exclusion zones on the surface,” Ferrenbach said. The system can also be a part of preemptive fire and heat-even mitigation measures.

With an expansion rate of up to 35 times the original volume, the foam is applied “using a high-volume delivery pump,” he said. Rocsil Foam reacts and cures within 90 seconds.

“Rocsil LS1 Foam plug seal system, used remotely, stands as the industry’s premier benchmark, offering a secure, cost-effective, and swift response to underground explosions, heating, or fire incidents,” Ferrenbach said. It is a “cost-effective solution for guaranteed sealing.”

By reducing downtime, it can help a miner improve productivity. “The use of Rocsil Foam to quickly address and neutralize underground fires reduces operational downtime and damage to mining infrastructure, thereby maintaining productivity and safeguarding revenue streams,” he said. “It’s efficiency in creating seals allows mining operations to resume more swiftly post-incident, minimizing economic impact.”

It can be used to limit the size of the no-go area. “By using this system, you can limit the isolation to the zone with the fire, rather than the entire mine,” Ferrenbach said. “When a fire occurs, the mine can either isolate the affected zone and continue operations elsewhere, or it may be forced to shut down completely.”

Per regulations of certain jurisdictions, a fire in a mine could trigger a mandatory mine closure that lasts months. “Therefore, the ability to quickly and efficiently isolate the fire zone is crucial for maintaining the mine’s productivity and revenue,” he said.

The system is relatively easy to use and requires comparatively minimal labor. As a part of preemptive fire and heat event mitigation measures, a mine-sealing plan would be “designed and engineered for optimal outcome,” Ferrenbach said. The plan would include pre-determined installation locations, which would allow “faster installation than reactive drill and remote sealing methods.” Hosing and application heads are run and fixed in place, and the required foam quantities are known in advance.

The result is a relatively quick and simple application. “A Rocsil Foam Maxi standard pump with bulk IBC product packaging is used,” Ferrenbach said. “This system improves pumping rates, reduces manual handling and has the added benefit of being a closed-circuit system, which reduces the likelihood of mine workers being exposed to chemicals,” he said. “Using this system product, equipment and crews can quickly be mobilized to site.”

Other benefits offered include improved safety over classic filling procedures and products. “By adopting Rocsil Foam technology, mining operations can dramatically enhance their safety protocols, effectively reducing the risks associated with underground fires and explosions,” Ferrenbach said. Remote control removes workers from a risky situation. “The remote sealing system allows for a Rocsil Foam plug to be pumped from a place of safety.”

The foam was originally created in the 1980s for cavity-filling after a roof collapse on a longwall. Since then, “the technology has been improved by various expansion ratios, safer chemistry and longer shelf life of the components,” company literature said.

“Rocsil Foam boasts a long-standing history of success in underground coal mines worldwide,” Ferrenbach said. “This product is widely used to secure open voids and cavities above longwall shields and along roadways.” The foam also “serves as an effective strategy for the restoration of collapsed roadways, facilitating the more efficient retreat of longwalls under adverse mining conditions.”

Its use as “a firefighting and safety solution in coal mining reflects a history of innovation aimed at overcoming the limitations of traditional fire suppression methods,” he said.

For example, one miner used it to create five “in-mine ventilation plugs, remotely placed, at depths of approximately 750 to 900 ft,” Ferrenbach said. “The first two structures were placed using two injection boreholes and two video-camera boreholes each,” he said. “The last three structures were each placed with a single injection borehole and a single video-camera borehole.”

The plugs were “backed up with stoppings and approved 50 psi seals,” he said.

Elsewhere, for a fire in a mine in West Virginia, eight plugs were installed. Each barrier was 90 m³. “The last plug to be pumped had more ventilation since all the other galleries had been sealed, so this one was done with 130 m³,” Ferrenbach said. “The injection of each plug was done in less than 2 hours, and the rescue team could access the mine 72 hours after the last plug was injected.”

For a more recent fire, the miner sealed “off the entire area and used nitrogen injection to contain it,” Ferrenbach said. “When it came time to re-enter the mine, they opted to isolate the section by constructing seven seal plugs with Rocsil Foam, each measuring 6 by 4 m.”

For each plug, three holes were drilled. One was for injecting the foam and the other two were for cameras. “They drilled to a depth of 1,160 ft,” Ferrenbach said. “Injection work on each plug took an average of 12 hours per day, with a planned volume of 150 m³ per barrier.”

Other, similar examples show how the evolution of Rocsil Foam “is marked by continuous improvement,” he said. “And application success stories from coal mines around the globe solidify its status as a best practice in the industry.”

Suppression System Saves Electronics

Johnson Controls launched the ANSUL N-101 Clean Agent Vehicle Fire Suppression System. The launch includes “the introduction of a sustainable, naturally occurring gas-based suppression system that has been tested and is fit for purpose in markets that typically require FM-5970 fire protection systems,” said Kristin Ryczek, global product manager, vehicle fire suppression systems, Johnson Controls.

Purpose-designed to protect energized electrical equipment inside unoccupied electrical cabinets onboard heavy industrial vehicles, the gas-based suppression system “is the ideal supplement to a complementary system, such as LVS and the ANSUL CHECKFIRE detection and actuation system,” she said. The new system addresses “a fire risk that has previously gone without coverage or has used other suppression agents that are under legislative review.”

The “system, in particular, gives the option to provide fire suppression to electrical components that are part of the critical production path on the machine that may otherwise go without fire suppression due to lack of a fit-for-purpose product for fire suppression,” Ryczek said. Using nitrogen, the system suppresses fire by reducing oxygen within the enclosed space.

“The nitrogen is stored within a pressurized container. Upon fire detection and subsequent release, the nitrogen passes through the valve, through the hydraulic hose distribution line, and out the 360° nozzle, discharged into the electrical enclosure or hazard area,” she said. “It floods the electrical enclosure quickly and efficiently, and reduces the oxygen content within that space, even when un-closable openings are present.”

The system has an operational range of -65°F to 210°F, a simplified single-tank, single-nozzle design, heavy-gauge steel bracket construction, and is engineered to withstand harsh conditions. With an electric-pneumatic actuator, the nitrogen container is available in two sizes, 23 ft³ and 55 ft³, to support a wide range of vehicle applications.

The N-101 system offers numerous benefits, foremost being improved business continuity “by limiting the damage caused by a fire within these types of enclosures, which would have otherwise been damaged,” Ryczek said. “Using CHECKFIRE, a fire can be detected and release the suppression agent, drastically reducing the amount of downtime from a fire scenario,” she said.

The simple design helps with the install and upkeep of the system. “The N-101 system uses naturally occurring gas as a clean fire suppression agent, has a simple method for design selection without typical hydraulic calculations for an engineered gaseous system, and provides scalability for larger pieces of equipment,” Ryczek said. “N-101 also doesn’t require sourcing a chemical agent or specific gas blend for system refills upon discharge like with other systems.”

A discharge leaves no residue or byproduct, ultimately making the system comparatively safer for workers, the environment, and electrical components. “Nitrogen is a great option for a suppression agent because it is a naturally occurring atmospheric gas and will return to atmosphere after the system discharges and the enclosure is ventilated, limiting any additional clean-up from the suppression agent required after the system discharges.” she said.

A discharge “will not cause damage to the protected electrical assets nor require clean-up, making it a better option for people, equipment and the planet,” the company said.

BEV Fire Suppression Blankets Contain Flames

“DENIOS introduced blankets for covering and suppressing large battery thermal runaway fires. “In the event of an accident involving a high-energy-density Li-ion battery, high-temperature fabrics provide sufficient fire containment and heat protection,” DENIOS said. “They contain the flames and reduce the risk of the fire spreading and associated collateral damage, until emergency response personnel arrive.”

The fabric has a mineral coating on both sides. “Double seam overlap with steel thread processing allows these blankets to withstand temps to 2,372°F (1,300°C)” in the short term and 2,102°F (1,150°C) for a longer period, the company reported. The fabric’s melting point is 2,912°F (1,600°C). Battery fires can burn at several hundred degrees Fahrenheit.

Less than a millimeter thick, the silicate fabric, which is 96% SiO₂, weighs 625 g/m². It is soft, flexible, non-itching and non-slip, the company said.

“The open-pored fabric allows the use of fire extinguishers and sprinkler systems to create a cooling effect, while limited gas (and smoke) permeability prevents the cover from ballooning,” DENIOS said. The fabric can trap pollutants released during thermal runaway, it said.

The four corner loops and reinforcement material is made of KA-2H fabric. The loops “allow the blankets to be quickly and easily deployed,” DENIOS said.

Available in three sizes, each with their own storage container, they “are capable of being reused between three to five times.”

The smallest, which is designed for electric compact car fires, weighs 7 lb, including case. The biggest weighs 91 lb including case. That case is 24- x 16- x 13-in., 13 gallons in volume, and weighs approximately 13 lb It has 2 wheels, a telescopic handle, a handle on the long side, and two handles on the front side.