Summary Report for Use of Positive Pressure Ventilation (PPV) Fans to Reduce the Hazards of Entering Chemically Contaminated Buildings

Firefighters have used Positive Pressure Ventilation (PPV) fans to remove smoke from buildings before entry for rescue operations. A study was conducted to determine their effectiveness in removing chemical vapors from a building to afford quick rescue in the event of a terrorist bomb that employed chemical warfare agents. The testing was conducted in two phases. The first phase examined the ventilation rates of the building in natural and forced air (with the PPV fans) modes to determine the improvement in ventilation when PPV fans were used, and to determine how much vapor can be purged from a building within the first 10 minutes of PPV fan use. The second phase examined a mock rescue scenario in the same building by filling it with methyl salicylate and measuring the Physiological Protective Dosage Factor (PPDF) that firefighters received while performing the rescue mission. This testing was performed according to standard Man-in-Simulant Test (MIST) procedures. Previous MIST testing of firefighter gear was used as a baseline to determine the increased protection obtained by using PPV fans. --Original contains color plates: All DTIC reproductions will be in black and white.