Vent 3 Information

Tempest MVU

Tempest Technology Corp. built the Mobile Ventilation Unit or MVU on the Positive Pressure Ventilation (PPV) principals. The MVU works by creating an air-seal at the entrance point, pressurizing the structure. The resulting airflow blows clean, fresh air into the structure, forcing out heat, smoke, gasses and other contaminates. It can be used to ventilate any size or shape structure as long as there is an entrance point for the clean air and an exit point for the contaminated air. It is a proven technique that saves lives, and improves worker and citizen safety (source: Tempest Technology Corp.).

Removing toxic gases and fumes from structures in post fire knockdown is a typical operation for portable fans and the MVU.  Applying the technology along with fire attack is a proven tactic that increases firefigther safety and victim survival.  The MVU is vital to victim survival in high occupancy structures for evacuation purposes as well as Positive Pressure Fire Attack (PPA).  Using the MVU immediately allows the unit to get in proper position and aid evacuation by providing a clear exit point for victims and a safe environment for firefighters.

Vent 3 is the first unit built on a Tempest's new light weight platform in the United States and has the largest rated capacity of any fire department ventilation unit in Western Pennsylvania. The fan unit platform has the ability to pivot 180 degrees and tilt 30 degrees for direct ventilation because placement for use without these features can be less than optimal.  A portable sock is carried to channel fresh air to the entry point when the unit is unable to hit the entry point direct.  The unit operates independent requiring no other support for operation, unless the optional misting ring is required where a water source and pumper are then needed.

Listed below are links demonstrating operation and some optional features of our mobile ventilation unit.  If you would like more information on this unit, please use the Contact Link on this website or visit Tempest Technology Corp. using the link below. 

 Links of Interest

 Informational Video

Direct Ventilation Video

Ventilation with Optional Sock Video

Optional Misting Ring Video

NIST PPV Testing Site

Other MVU PPV Links

KDKA St. Sebastian School via Tempest website


2007 Ford F450 4X4/Tempest MVU

Carries up to 5 Firefighters
MSA SCBA Units (4)
Ventilator Specs:
48 inch Impeller Diameter
123,500cfm Air Flow
180 degree Rotation
30 degree Tilt Mechanism
70gpm Misting System
100ft of Sock for Fan 

How does the MVU work? 


In a typical MVU application, the blower is placed about ten to twenty feet from an opening of the structure. It is positioned so that the cone of air produced by the blower completely seals the opening. If the MVU is unable to position for direct blower access, then a tube may be used to channel the blower output to desired location.  Once the doorway is sealed, air pressure inside the structure builds almost instantly. An exhaust opening, ideally 2X the entry (or ventilation) point, allows the air to quickly escape due to the difference between the outside and inside air pressure. The smoke, toxic fumes and other contaminates are quickly cleared and replaced with fresh, clean air. The Tempest Power Blower’s unique shroud design creates the cone of air that is essential for PPV to work. The MVU concept is no different than using small power blowers.  

Picture and concept courtesy of Tempest Technologies

 Action Photos


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