In 2018 more than 58,000 fires burned nearly nine million acres across the U.S. More than 25,000 structures were destroyed, including 18,137 residences and 229 commercial structures.

At $3.6 billion in insured losses, Fort McMurray 2016 wildfire is the costliest event in Canadian history. An estimated 88,000 people were evacuated. Hundreds of structures were destroyed by fire, including 2,579 homes and other dwellings. The estimated financial impact of the fire was $8.9 billion in Canadian dollars.

With recent increases in wildfire activity have come an increase in damages due to wildfire. As well, wildfires have become increasingly destructive to private property. In 2020, almost 18,000 structures burned in US wildfires, including almost 10,000 homes. Fifteen of the twenty most destructive fires in California state history as of July 2021, in terms of structures of destroyed, have occurred since 2015.

One of the techniques that is used to increase the chance of structures to survive in a wildfire situation is using exterior fire sprinkler systems. Outdoor sprinklers are not a replacement for other preventive measures recommended by Fire Wise or Fire smart programs but if implemented properly and at the right time, they could be very effective.

According to USFA and FEMA, Wildfires spread primarily by:

  • Ember generation and deposition. Burning or smoldering pieces of material generated during a wildfire event can land on combustible material.
  • Radiant heat. The heat from the fire raises the heat of a combustible material until that material reaches ignition temperature and burns.
  • Flame impingement exposure (conduction). The flame from a fire touches a combustible material and the material burns.
  • Convection. The transfer of heat by moving hot gases ignites combustible material.

Of these 4, embers (sometimes also called firebrands or flaming sparks) contribute to a significant percentage of home ignitions. These pieces of burning material lofted into the air by winds generated during the wildfire event can be small or large.

FireSmart Canada and FireWise US provide valuable advice and guidance on preparation work that increase the chance of a structure to survive a wildfire event. The focus of these programs is primarily on limiting the amount of flammable vegetation in the home ignition zones.

Please see following from FireSmart Canada for definition of home ignition zones.

FireWise US has similar definitions for the most part but the naming of the zones is different:

  • Immediate Zone: 0 to 5 feet around the house
  • Intermediate Zone: 5 to 30 feet
  • Extended Zone: 30 to 100 feet

S-DRU wildfire protection consists of a water tank, high pressure/high flow fire pump, high pressure water hoses, High flow wheeled wildfire sprinklers, adjustable flow high pressure fire nozzle, wildfire prediction module and a pump for filling the tank.

S-DRU wildfire protection system is designed for quick utilization at filed without requiring any special tools and having a basic fire fighting skills would be more than enough to set up and use the system. Although the best results could be achieved if it is used by professional firefighters, the unit is designed so it could be used by any resources available during emergency.

S-DRU is equipped with three solutions that could improve the resilience of communities against wildfires if they are used in conjunction with preparation work recommended by FireSmart Canada and FireWise US.

Direct attack

This option could be very effective in covering fires in Zone 1a (Immediate Zone), Zone 1 (Intermediate Zone) and Zone 2 (Extended Zone), specially if it is used in early stages.

The mobility of the trailer coupled with the latest technology fire nozzle and light weight fire hoses provide high degree of flexibility to meet the dynamic filed conditions during an emergency.

All the components which are used in standard design of S-DRU are compatible with addition of foam system and/or eco-friendly fire-retardant injection when/if needed.

Mobile Wheeled Sprinklers (High flow/Long range)

This option provides the best results in increasing the resilience of structures and surrounding vegetations when used in advance of a wildfire reaching to the area. The high flow long range wheeled wildfire sprinkler in conjunction with the mobile trailer, make this option suitable for covering all ignition zones (Zone1a, Zone 1, Zone 2 and Zone 3).

Once activated, the system does not require any intervention and can function on its own. High flow long range wildfire sprinklers could reduce the impact of fire embers by creating a microclimate around the structure and wetting the dry surfaces to reduce the chance of ignition.

Automatic Sprinklers

This option includes using an electric pump that is energized by ESS and does not rely on any external sources for power or activation. The pump has two functions:
a. Filling the Tank automatically using level sensors when a source of water such as river, pool, lake, or city water is available.
b. Activating a fixed wildfire sprinkler system located on the unit

This option is suitable for protecting Zone 1a (Immediate Zone) and Zone 1 (Intermediate Zone) for smaller structures and when local presence could put the safety of the crew in danger. The system could be activated through Sunact Systems App remotely from several kilometers away if needed.

The size of the tank, the length of the hoses, power of the pumps and type of sprinklers would be selected based on customers application. The function of an exterior sprinkler system is to minimize the opportunity for ignition by wetting the home and surrounding property. Ignition of combustibles located on or near the home can result in a radiant and/or flame contact exposure. Water should reach all vulnerable areas for the system to have maximum effect both on and near the home.

The three protection methods which are provided by S-DRU are designed to provide additional protection layers against the three basic wildfire exposures: wind-blown embers, radiant heat, and direct flame contact.

Although most of these protection layers are not perfect if used alone, a combination of all of them, as presented by S-DRU could increase the chances of surviving a wildfire significantly.

The simple and flexible design of S-DRU allows it to be used by professional responders or members of community alike.

Search and Rescue

S-DRU could also be integrated with a fix or drone based thermal imaging system that provide the required data for the system to create a thermal model of the area.

The thermal model could be used for improving the efficiency of sprinkler system, planning activities, monitoring the dynamic field condition and support search and rescue efforts for finding survivors when/if needed.