Physiological Evaluation of First Responder Mask

The First Responder Mask (FIRM) was developed for domestic preparedness/counterterrorism personnel (e.g., firefighters, police, medical support, search and rescue, security, investigators) to provide at least 12 hr of continuous protection against chemical/biological exposure when a terrorist incident or chemical emergency required their participation. It is a powered air- purifying respirator with adjustable hood, nosecup, and one-size-fits-all neck dam configuration. This physiological evaluation of the FIRM tested its suitability for human use prior to submission to the National Institute for Occupational Safety and Health for certification. The mask provided adequate filtered ventilation for sustained heavy workloads. Oxygen and carbon dioxide concentration within the FIRM remained at or near ambient levels during rest and exercise with the blower on. With blower off or loose nosecup, the oxygen concentration fell to 20.2% and carbon dioxide rose an average of 0.29% over the 20-min test period. This would allow ample time for anyone in a contaminated area to reach safety when a blower fails or the battery is discharged. Visual acuity, color acuity, depth perception, field of view, and contrast sensitivity wearing the mask were essentially the same as the unmasked control values in the same subject. A commercial soda/water bottle can be connected to the FIRM's drink tube fitting. The original document contains color images. All DTIC reproductions will be in black and white.