December 22, 2016

CNAS Press Note: Army Shelves Blast Gauges to Protect Soldiers’ Brains

The U.S. Army recently shelved blast gauges that it had issued to troops in order to assess mild traumatic brain injury (TBI) from harmful blast waves. The gauges identified that troops are routinely exposed to harmful blast waves from firing heavy weapons. In a new Press Note, Center for a New American Security (CNAS) Senior Fellows Phillip Carter and Paul Scharre argue that the decision hampers attempts to better understand TBI and harms military servicemembers.
The full Press Note is below:
Over 350,000 military servicemembers suffer from traumatic brain injury (TBI), the signature wound of today’s wars. TBI is poorly understood, and can be caused by concussions, explosions from improvised explosive devices (IEDs), or blast waves from firing heavy rifles and artillery. The brain can even be harmed by repeat small exposure to concussions or blast waves. Over 80% of servicemembers diagnosed with TBI have mild TBI, a latent injury that is difficult to detect. Even mild TBI can damage brain functioning, causing memory loss, poor concentration, depression, and irritability. 
Blast gauges, like those the Army deployed in 2011, are a vital tool for improving the military’s understanding of TBI, particularly because small, repeat exposures can accumulate damage over time. Demonstrating their value, these blast gauges identified that soldiers are routinely exposed to harmful levels of blast overpressure from firing artillery, anti-tank recoilless rifles, and heavy caliber weapons. These findings are not surprising. Experiments have demonstrated that pigs exposed to as little as three blasts from artillery, anti-tank weapons, and .50 caliber rifles suffer mild brain injury. During training, soldiers may experience 30 to 300 exposures a day, several days per week.
More data is needed to better understand how routine blast exposure from firing weapons may damage servicemembers’ brains. Mild TBI symptoms may not become evident until years after a servicemember has been injured, making data collection essential. Data on blast exposure will help veterans receive the care they need after they leave military service. It will also assist future medical studies in evaluating the link between repeat blast exposure and TBI. Unfortunately, the Army has decided to stop collecting data that shows that servicemembers may be routinely exposed to harmful blasts during training. Rather than attempt to understand brain injury, this decision hides from data and harms military servicemembers as a result.

Carter and Scharre are available for interviews. To arrange one, please contact Neal Urwitz at 202-457-9409 or


  • Phillip Carter

    Former Senior Fellow and Director, Military, Veterans, and Society Program

    Phillip Carter was the former Senior Fellow and Director of the Military, Veterans, and Society Program at the Center for a New American Security. His research focused on issu...

  • Paul Scharre

    Executive Vice President and Director of Studies

    Paul Scharre is the Executive Vice President and Director of Studies at CNAS. He is the award-winning author of Four Battlegrounds: Power in the Age of Artificial Intelligence...