UL Firefighter Safety Research Institute – In episode 17, learn more about why if you get water where it needs to go, you don’t need much from UL FSRI Advisory Board Member, Chief of Central Whidbey Island Fire Rescue, Ed Hartin.
Room and contents fires are most commonly ventilation limited – meaning that the energy release rate is limited by the available oxygen. It does not take a large amount of water to absorb the energy being released and to knock the fire back so that suppression can be achieved. If the attack crew can get the water where it needs to go – they won’t need much. Keep in mind, using less water does not relate to more effective suppression. In instances where an interior suppression is chosen, more water used on the approach to the fire relates directly to more tenable conditions for potential trapped occupants and suppression crews. Also, during these experiments most of the water flow was scripted with leeway given based on conditions experienced by the nozzle firefighter, so the intent of this section is not to propose that a particular type of attack is more efficient. The intent is to highlight that, even at high flow rates (150 gpm to 165 gpm), both transitional attack and interior attack using the reach of your stream to cool as you advance do not require much water to improve conditions.
The multitude of potential variables on the fire ground will often complicate operations more than the scenarios tested. Establishing a water supply and deploying a backup hand line are two critical steps to help provide a safety factor to the operations on the fire ground in the event the primary attack line encounters difficulty applying water directly where it needs to go.
For more on this Tactical Consideration, visit the “Study of the Impact of Fire Attack Utilizing Interior and Exterior Streams on Firefighter Safety and Occupant Survival” project page to access the research reports and online training.