SNFO 12 Positive Pressure Ventilation.pdf

Southern Nevada Fire Operations (SNFO) STANDARD OPERATING PROCEDURES EMERGENCY OPERATIONS POSITIVE PRESSURE VENTILATION Effective date: Supersedes: SOP# SNFO-12 2/17/2016 N/A Page 1 of 4 PURPOSE This procedure identifies the application of positive pressure ventilation during structural fire operati...

Southern Nevada Fire Operations (SNFO) STANDARD OPERATING PROCEDURES EMERGENCY OPERATIONS POSITIVE PRESSURE VENTILATION Effective date: Supersedes: SOP# SNFO-12 2/17/2016 N/A Page 1 of 4 PURPOSE This procedure identifies the application of positive pressure ventilation during structural fire operations. The proper use of positive pressure ventilation (PPV) has many benefits to fire operations. They include: A. PPV rapidly removes heat and smoke from the building. B. Rapid removal of smoke improves firefighter’s ability to conduct search and rescue operations. C. The improved atmosphere and visibility increase the firefighter’s ability to conduct the attack/extinguishment operations. D. PPV creates a safer atmosphere – thus improving patient survivability and creating a safer environment for firefighting operations. E. The improved atmosphere reduces fire fighter heat stress. F. PPV reduces loss caused by smoke and fire damage to the structure. No tactic should be applied in every case and all tactics have tradeoffs. Coordinated, purposeful PPV will make the fire ground safer. PPV that is performed in an uncoordinated manner or misapplied by a Firefighter can be dangerous. SCOPE This procedure applies to all fire department suppression personnel. RESPONSIBILITY It is the responsibility of all fire department personnel to follow the procedure. POLICY All FD suppression personnel shall follow all safety precautions when conducting ventilation with positive pressure fans. Southern Nevada Fire Operations (SNFO) STANDARD OPERATING PROCEDURES EMERGENCY OPERATIONS POSITIVE PRESSURE VENTILATION Effective date: Supersedes: SOP# SNFO-12 2/17/2016 N/A Page 2 of 4 PROCEDURE All engine companies are equipped with high volume positive pressure fans. Offensive fire operations often qualify for early application of PPV, as part of a coordinated fire attack. Command should order PPV where appropriate and early in the operation. Engine Companies should expect to apply PPV and crews should dismount apparatus planning to take fans to the point of entry. 1. PPV Placement A. Positive pressure fans should be placed at the point of entry. B. The objective is to create a pressure “cone” effect around the door. The fans position should also allow access for crews entering the building. Normally the fan will be placed 6-10 feet from the entry doorway. 2. Tactical Considerations Positive pressure ventilation is effective only when applied properly. Two major items are required: A. An “exit” for the pressurized air must be provided and should be located in the fire area, prior to applying positive pressure into the structure. Vent opening will be completed prior to crews entering the structure. This is generally a window, door, or other opening of sufficient size in relation to the entry port. B. Positive pressure ventilation should be applied from the unburned side of the fire, when conditions allow. C. Wind: The vent opening shall not be created on the windward side of the structure. D. If the initial fire attack crew is unable to access the fire and apply water within 2 minutes after entry, the fan should be shut down or turned away from the entry port. This will afford the interior crews the opportunity to reevaluate the conditions and locate the fire. This shall be coordinated and communicated with interior crews. This step may also be repeated as needed until water is on the fire 1. No continuous PPV operation should take place if the location of the fire is not known and water is not being applied to the fire. a. i.e., concealed spaces such as sub-floors, walls, utility chases, attics, etc. It will be the company officers responsibility to ensure that PPV is working effectively prior to entry. Southern Nevada Fire Operations (SNFO) STANDARD OPERATING PROCEDURES EMERGENCY OPERATIONS POSITIVE PRESSURE VENTILATION Effective date: Supersedes: SOP# SNFO-12 2/17/2016 N/A Page 3 of 4 3. Initiating PPV Operations for Fire Attack The following benchmarks are required to be completed and communicated prior to initiating PPV on the fire ground: A. If it is determined (through size-up) that PPV is the appropriate ventilation tactic, the IC will announce an offensive fire with PPV. B. The Fire Attack crew will pull a hoseline, place it at the point of entry and charge the line. C. A proper exit port will be located, opened up and announced on the radio. D. PPV in place and pointed into the entry port. E. A determination that ventilation is effective (smoke following a path away from crew) 1. To make this determination it takes at least 15 seconds or more of uninterrupted air flow from the PPV fan. a. Crew must be patient! 4. Controlling Air Flow A. Air flow from PPV must be controlled throughout the operation. In some cases, windows and doors that are already open may need to be closed to direct the air flow into the fire area, or the most densely affected smoke area. B. As one area is cleared of smoke, it may need to be sealed off so that other areas of the structure can be systematically cleared of smoke via exhaust exits and directed air flow (PPV). C. All crews with interior assignments must maintain fire attack corridor integrity. 5. Multi-Story/High Rise Multi-story or high-rise fires require greater coordination and additional fans. A. Although high-rise buildings may have smoke management systems already in place, supplemental PPV operations may be required. This is due to the fact that smoke management systems do not evacuate smoke; they contain it and prevent its spread to other areas of the building. Smoke removal will most likely be performed by the Ventilation Group. B. Stairwells may be used to direct air flow from PPV. An exit in the fire area (i.e., window) is a good first choice. In some situations, a stairwell on the opposite side of the fire area can be used. An exit for the exhaust must be obtained. A roof door would be appropriate. C. Multiple fans may be required. Two or more fans may be needed at the base of the building. Additional fans may be needed on landings at various levels in the stairwell. A fan will be needed at the entry to the fire door. Southern Nevada Fire Operations (SNFO) STANDARD OPERATING PROCEDURES EMERGENCY OPERATIONS POSITIVE PRESSURE VENTILATION Effective date: Supersedes: SOP# SNFO-12 2/17/2016 N/A Page 4 of 4 D. Multi-story and high-rise positive pressure ventilation is complex. A Ventilation Group should be established to coordinate all aspects of PPV on all floors, working closely with the building engineers to maximize the use of built-in ventilation and smoke control systems. 6. Positive Pressure for Exposure Control In some cases, PPV can be used for exposure control. This is most effective with common attics (i.e., strip shopping centers, apartment complexes) or where separating walls may have been breached (i.e., plumbing, cracks, etc.). 7. Large Buildings Buildings with large square footage may require multiple fans at more than one location to effectively remove smoke. These situations are more complex and require close coordination of PPV with all company officers. Command should consider a Ventilation Group to coordinate all ventilation operations in large buildings. Note: “Big flow good, small flow bad” (Larger structures require larger amounts of air to properly pressurize and move smoke) 8. Precautions Positive pressure ventilation can create problems if not effectively managed and coordinated. Be aware of the problems listed below and take corrective action. A. NO Ventilation should be conducted until a fire attack crew is ready; a hose line is in place and charged. B. PPV should be correctly coordinated and evaluated prior to the fire attack team making entry. C. An exit should be in the burned area or the fire may extend into unburned portions. D. Because of positive pressure, the effect of fire blowing out of the exit may occur. This is normal and predictable; adjacent exposures may need to be protected. E. Do not direct a fire stream into an operating PPV exit point. F. All concealed spaces need to be checked for extension. G. Company officers will be responsible for monitoring and coordinating the application of PPV. H. The gas powered fans produce carbon monoxide and breathing apparatus should be used when PPV is used during overhaul operations. I. After initial knockdown, PPV should constantly be monitored so smoldering fires don’t advance. J. If openings are made after crews have entered a structure without proper PPV in place, there is an increased risk of exposing those interior crews to high heat and possible flashover.