Critical Infrastructure: Using Fiber Optic Sensing to Address Threats

Fiber optic sensing is a new tool that may address threats

• By Thomas Cohen
• Aug 10, 2017

For businesses, institutions and governments, securing sensitive areas and facilities is a constant concern. Standard practice today is to use barriers and visual monitoring and even security guards. But, these approaches may prove insufficient or not cost-effective.  That is why an increasing number of public and private entities are including fiber optic sensing technology in their security tool chest. By having fiber optic sensing technology at the perimeter of a facility or site, you can detect footsteps of intruders in real time, detect vehicles and other activities away from the fence, monitor with 24/7 x 365 coverage all along the perimeter, with no gaps, even over several miles or have all activity and alert data stored for review and forensic analysis if required. 

All of this information can then be gathered, analyzed and delivered to the security team’s leadership, allowing them to plan accordingly and neutralize the threat as quickly as possible.

As threats become even more complicated and persistent, fiber optic sensing offers vital solutions that security professionals can use.  

The Backstory

Fiber optic sensing, which has existed for decades, uses deviations of light in fiber optic cables to remotely measure acoustics, temperature, strain and vibration. With this remarkable technology, the entire length of the cable serves as a sensor, and with continuous refinements, the value of the technology has increased substantially. As such, it provides a great fit for securing sensitive areas and for being used in a wide array of other applications. The global fiber optic sensors market is expected to grow by about 10 percent annually and should reach $3.2 billion by 2021, according to a market research report by BCC Research. 

Applications

Today, fiber optic sensing is used to monitor thousands of miles of international borders, critical infrastructure, and sensitive facilities in transportation, security, oil and gas, energy, military, and medicine. It provides 24/7 monitoring of perimeters around military installations and other government facilities, institutional sites, and key community infrastructure.  It also can be used in residential neighborhoods, and at resorts. 

Fiber optic sensing technology additionally can detect pipeline leaks, rail integrity, digging, tunneling, seismic activity, unsafe temperatures, crumbling infrastructure and other conditions.  All of these conditions can be monitored real time from miles away and can be coordinated with other monitoring equipment, including security cameras, microphones, helicopters, and even fleets of drones. Alerts can be sent any time night or day.

Numerous Applications

Pipeline operators have been early adopters of this technology, with approximately 30,000 miles of pipeline around the world protected by fiber optic sensing today. One example is the Baku-Tblisi-Ceyhan pipeline, which uses fiber optic sensing to monitor leaks, intrusion, and seismic activity occurring over a distance exceeding 1,000 miles. In the United States, Southern California Gas announced plans earlier this year to install fiber optic lines along all of its new and replacement lines. Continuous monitoring and measurement will quickly identify threats to a pipeline from heavy equipment operation, unexpected earth movement, or physical impact.  When a threat is identified, information will be sent within seconds along the fiber cable to a remote monitoring station. The system can pinpoint within 20 feet where a potential problem may be developing.

There are energy applications as well. In the United Kingdom, distributed temperature sensing is protecting 154 km of cables that move electricity from the Greater Gabbard Offshore wind Farm to the shore. A displaced cable, whether resulting from a seismic shift, anchor drag, or vandal, will immediately alert operators. Fiber optic sensing is now routinely used to monitor the integrity of nuclear power plants, where failure is unacceptable. 

In the rail sector, a major test is occurring with the Federal Railroad Administration in Pueblo, Colo. to understand how fiber optic sensing can detect broken rails, flat wheels (which damage rails), train movements and staff activity near the track.  Rail operators in Washington, D.C. and San Francisco are preparing for their own trials.

Fiber optic sensing is also being trialed in “smart roads,” an application where embedded sensors in roadways share data with connected cars. One company, Integrated Roadways, is working closely with the state of Missouri to explore the possibilities. One could envision fiber optic sensors helping police track fleeing drivers, detect trespassers on closed roads, and monitor traffic around military and power facilities.

Beyond smart roads, fiber optic sensing is increasingly used in smart infrastructure projects around the globe.   As an example, the technology is playing a critical role in infrastructure development in London, a task made tricky by the city’s age and location on the banks of the Thames.  In the Crossrail railway project – currently the largest construction project in Europe – fiber optic sensing is used to monitor a number of key elements, including an 84-meter deep diaphragm wall used to hold back Thames River water, the movement of masonry arches at London Bridge Station during extensive piling work occurring beneath the station, and the integrity of the 100 year old former Royal Mail Railway tunnel during construction of Crossrail’s Liverpool Street Station tunnels very close beneath.

Increasingly, companies are using fiber optic sensing for traditional perimeter security. One of the latest deployments involves a high-end golf course in the northeastern United States.

The Technology and Equipment

So, how does the technology work? First, it makes use of the amazing properties of fiber optic cable. Self-contained, ecologically friendly and sealed from the elements, fiber optic cable is lightweight, non-electrified, and invulnerable to electromagnetic interference like chip-based sensors. Fiber optic cable is resistant to high temperatures and can be used near high voltage and flammable material since it does not create sparks. 

In addition, the technology makes use of the fact that strain, temperature, and sound waves changes the reflected light in fiber optic cables. The technology also can accurately read activity and conditions along the cable for 25 miles or more. 

As an example, distributed acoustic sensing (DAS) employs dedicated monitoring/alerting hardware and software connected to the cable. Pulses of light are sent down the cable.  Returning “backscatter” or reflected light is “interrogated” for changes due to acoustic energy.  Every type of noise event creates a distinct acoustic signature, enabling systems to quickly learn to distinguish important signals.

Software displays processed information in a browser and can plot alerts on a map. DAS can be integrated with closed circuit TV and distributed temperature sensing (DTS), which is often used in pipeline, industrial, power generation and mining settings. One application is monitoring the temperature of important power cables.

So what will it take to roll out the technology everywhere?  Increasing public, industry, and government awareness is certainly a key element, and that is why 12 companies formed the Fiber Optic Sensing Association (FOSA) this past April. Founding members include AFL, Corning Incorporated, Ditch Witch, Dura-Line Corporation, Fotech Solutions, Frauscher Sensor Technology USA, Integrated Roadways, OFS, Omnisens, OptaSense, OZ Optics and Prysmian.  FOSA is dedicated to educating the security and other sectors about the opportunities that fiber optic sensing technologies can and will provide, and we welcome all to join us in this effort, especially those who are charged with protecting physical security. As your concerns mount, deploying fiber optic sensing technology can provide an effective solution efficiently and can make the difference in thwarting an intrusion or disruption. That’s an opportunity that should be seized.