High-powered fans are used to improve visibility inside an engaged building by quickly removing smoke. Positive pressure ventilation (PPV) is a fire service tactic that can enhance rescue efforts by helping remove smoke and toxins from a structure.
PPV can create an improved environment, with less risk of injury to the rescuers and a clearer path to the seat of a fire, which ultimately may improve conditions for fire and rescue attempts.
PPV may also decrease the losses caused by smoke damage to a structure.
What is a PPA technique?
A positive pressure attack combines mechanical positive pressure ventilation to remove smoke before fire control and prior to advancing into a building for victim rescue.
PPV fans create higher pressure inside the building, which forces interior air out of the structure through an exit hole when lower pressure builds. PPA can decrease a fire’s ability to spread and advance.
Are There Times When You Should Not Use a PPV Fan?
PPV fans can only work as a fire rescue tool if only two openings exist in a structure. They should not be used when a structure is fully involved.
They are best used for removing smoke from a room or structure when there are no longer extreme heat conditions present and no threat of flashovers. In other words, they are best used post-fire.
PPV Fan Placement
Your PPV fan should be placed wherever there’s a need to remove high heat from an area and increase visibility inside the structure. PPV placement is typically 4-10 feet outside the structure doorway or opening. Consult your fan specifications, noting the suggested setback for optimal airflow.
What are Examples of Positive Pressure Ventilation for the Fire Service?
We carry Stream Shaper PPVs, like the popular Super Vac Valor Series Gas PPV, with guard options that create a positive pressure effect. The StreamShaper Guard has a narrow air stream, which creates more pressure in front of the fan stroud, ideal for departments that need precise airflow, usually in high-rise buildings and floorplans with numerous small rooms. This guard can be set farther from the building entrance, leaving more room for personnel to enter and exit the building.
Prefer a battery-powered PPV? Check out the Milwaukee Super Vac V16-BL Series, providing up to 40 minutes of max airflow, depending on Milwaukee M18 battery selection. Thanks to this easy-to-source battery found in many other firefighter battery-operated tools, this fan has become a favorite for its compatibility. This fan is super lightweight and compact in size, so you can store it in narrow areas.
How to Purchase a PPV fan
Positive pressure ventilation must be properly managed and monitored to prevent a “blow torch” effect. Also, gas-powered PPV fans can produce carbon monoxide, so monitor their impact on the need for breathing apparatuses. More than one PPV fan may be needed depending on a building’s square footage. Read the manufacturer’s specifications on your PPV prior to purchase. Contact us for more information.