An industrial fire does not have to be a towering inferno to be both destructive and expensive. Operational infrastructure needed to run a plant or factory can be easily be disrupted by a fire just big enough to gut a control box the size of a vending machine.
Automatic fire suppression systems that use inert gas to suffocate these fires are nothing new. However, a Netherlandsbased fire suppression company has developed a system that eliminates the need to keep that inert gas in high pressure storage tanks at the ready.
The technology to generate ample nitrogen for extinguishment using a solid source comes courtesy of the European Space Agency, said Edwin Verver, chief commercial officer with EXXFIRE BV.
“Basically, it is a small rocket engine using solid propellant,” Verver said. “In our case it is very low thrust and low pressure, generating nitrogen at ambient temperature. So the beauty of it is we store the gas in solid form.”
In space, cool gas technology is used to re-pressurize propellant tanks used to steer orbiting satellites. On Earth, the same technology is used to generate nitrogen needed for the EXXFIRE fire suppression system.
“The gas is generated within four to 30 seconds of activation, depending on the size of the generator” Verver said.
Rather than an explosive pressure release, the nitrogen is released in a steady buildup at low pressure. The gas released is at room temperature as opposed to comparable devices such as car airbags that emit heated gas, Verver said.
The EXXFIRE fire suppression system eliminates the residue left by dry chemical extinguishers or aerosols. Likewise, there is no risk of water damage as with mist systems.
EXXFIRE is a modular system specifically designed for cabinets and server racks. It does not require the robust piping used in pressurized systems, relying instead on lightweight tubing. The unit can be installed either inside or outside the protected enclosure.
Installing and maintaining pressurized fire suppression systems tend to be labor intensive compared to EXXFIRE, Verver said.
“They have valves and gauges that need to be checked every year,” he said. “Every ten years the entire system must be hydrostatically tested. Cool gas generators require none of the above.”
EXXFIRE gas generators have a 15-year life span. A single EXXFIRE 750 gas generator can produce 0.95 kg (slightly over two pounds) or 750 liters (198.1 gallons) of nitrogen enough to protect 1,2 cubic meters. EXXFIRE’s largest unit, the 5000, is be expected in 2016, producing 5,000 liters (1320 gallons) of nitrogen to protect 8 cubic meters. With 12 of them you can protect a room as large as 100 cubic meters (26,486 cubic feet).
Pure nitrogen is environmentally friendly, depleting neither the ozone layer or contributing to global warming. The solid material used to generate that nitrogen remains inside the generator and can be recycled.
Depending on placement of the unit, EXXFIRE uses aspirating detection with three optical sensors and their own in house developed software based on XP95 protocol.
“When we have double confirmation for at least two sensors, the generators deploy enough gas to lower the oxygen level inside the confined space to below 15 percent,” Verver said.
While the detection equipment uses fully certified components, cool gas technology is still so new that the appropriate testing standard have yet to be written, he said.
“We have tried to design our systems as close to existing standards as possible,” Verver said. “There are no standards yet for this type of system.”
Plans call for EXXFIRE to compile reference data from its first units sold, he said. EXXFIRE is currently building its first 500 units with 400 units already sold.”
“About 200 are capable of being deployed without any approvals,” Verver said. “These have been sold to companies that believe in the technology without requiring approvals. “
The remaining 200 units being sold will require certification by testing agencies before installation, he said.
“We are talking already to Underwriters Laboratories and VDS to determine to what extent they can certify our products,” Verver said.
EXXFIRE’s first products are expected to hit the fire protection market by the end of the year.