Written by Casey Grant, Fire Protection Research Foundation | 03 February 2011 
Safety is everybody’s business. A poor design or installation of a solar power system can create an unsafe condition that results in a black eye for all of us. The first step is to understand the safe use of solar power technology.
Electric shock is a serious threat to fire fighters. Each year, for example, in the US an average of 215 fire fighters are injured by electric shock while engaged in fireground operations at building fires. But how many of these injuries involved solar power? The answer is we don’t know, as data collection currently doesn’t address whether photovoltaic (PV) power systems were involved. But fire fighters recognize the potential risk, and thus it is important for all solar power professionals to work with their local emergency responders to adequately understand and mitigate perceived risk.
Electric shock is a serious threat to fire fighters.
Fires that involve solar power systems can be one of three basic types depending on the point of ignition: (1) an external exposure fire to a building equipped with a solar power system; (2) a fire originating within a structure from other than the solar power system; or (3) a fire originating in the solar power system as the point of ignition.
From a fire service perspective, the comparable hazards between thermal systems and photovoltaic systems are generally similar with two noteworthy exceptions: a PV system includes an electric shock hazard, while a thermal system includes potential scalding from hot fluid. As with any structural fire attack, it’s best for the fire fighters to be aware that a solar power system exists on the building. If this is known, fire ground personnel can take appropriate precautions.
The major difference between a PV system and solar thermal system is that a PV system can remain energized while the fire fighters battle the blaze. One of the first steps fire fighters take is to completely shut off all electrical power to the building. But on a sunny day, they may not be able to shut off the power in a PV system. Large PV systems on commercial buildings are a particular concern to the firefighter, based on the amount of electrical energy and the corresponding hazard. An additional electrical concern exists for systems that have optional electrical storage batteries that can maintain electrical current at nighttime when the rest of the system has been isolated, and can present leakage and hazardous materials concerns if damaged in a fire.
Fire fighters have several other concerns relating to solar power in addition to electric shock. During roof operations fire fighters will need to consider the additional weight of the PV array on a roof structure that may be weakened by the fire (more so with thermal power systems). A rooftop solar array may also prevent direct access to the section of roof providing the optimum point of ventilation. The hazard of tripping or slipping is always a concern for fire ground operations on a rooftop, especially in dark or smoky conditions. Overhaul is the fire fighting activity that involves final fire extinguishment, and certain solar power components can pose unexpected clean-up/hazmat issues.
One of the best ways to learn about solar power is to live with it, and there are many fire departments that have installed solar power systems. One reason to use solar is that, in the event of disaster and loss of power, Independence from the electrical power grid can enable a fire house to stay up and running. A specific example is the City of Boston using PV for evacuation routes out of the city for critical traffic controls, gas station pumps, emergency evacuation repeaters, etc. The US Forest Service has often used PV systems for their remote fire service facilities.
It’s best for the fire fighters to be aware that a solar power system exists on the building.
The use of vehicle-mounted solar panels already exists within the fire service. In particular, an approach gaining traction in California is solar powered fire apparatus, which can come in handy when it’s deployed over a long period of time, such as when fighting a wildfire. This provides them with a dependable electrical power supply for radio operation and other critical electrical equipment, and supplements the energy provided from conventional fuels that need periodic replenishment.
The future of solar power technology looks bright. While this technology introduces new and different hazards for fire fighters, they are able to handle it with proper training and understanding. The fire service itself is a beneficiary of this technology, and working together we all win when we recognize that safety is everybody’s business.
About the Author
Casey Grant is Program Director of the Fire Protection Research Foundation in Quincy, MA. He is the author of “Fire Fighter Safety and Emergency Response for Solar Power Systems”, a 2010 DHS/FEMA Fire Grant funded study to address fire service safety issues relating to solar power systems. The report is available at: www.nfpa.org/assets/files/PDF/Research/FFTacticsSolarPower.pdf.
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