Applied Research Associates, Inc. (ARA) has long been at the forefront of research for blast effects on the brain, bringing together multidisciplinary teams to advance our understanding of injuries and brain health.
The range of brain health-related work that has been conducted at ARA over the last 20 years has helped protect the Warfighter and furthers ARA’s vision to serve as a company that government and industry turn to for innovative technologies and solutions to critical human problems that will make our world safer, make us more secure, and make a difference in our daily lives.
ARA’s research has helped inform the Blast Overpressure Safety Act, a bipartisan bill that was recently introduced in congress to direct the Department of Defense (DoD) to enact several measures to help mitigate and better protect service members from blast overpressure. The bill also aims to improve research regarding Warfighter brain health and expand access to treatment for service members and veterans.
Efforts by ARA and its DoD partners also played a role in the creation of DoD Blast Overpressure Reference and Information Guide (D-BOP-RIG), recently released by the Defense Health Agency to provide DoD guidance for managing brain health risks from blast overpressure in training.
ARA is the key partner the medical and military communities look to for leading-edge health solutions, and our team is at the forefront of research into personal protection and traumatic brain injuries. ARA pairs innovation with in-depth knowledge of physical, chemical, physiological, and biological processes to solve complex health problems.
ARA Principal Engineer Suthee Wiri, who has a doctorate in chemical engineering, is an expert in air blast effects, blast environments, and mitigation. Principal Engineer Christina Wagner, who has a doctorate in biomechanical engineering, is an expert in blast and biomedical engineering. Wiri and Wagner answered six questions about blast and what ARA is doing to investigate and address its harmful effects.
1. Can you briefly explain what air blast is?
Wiri: Air blast occurs when energy is suddenly released by detonating high explosive or as commonly seen in training, burning propellant leaving a gun muzzle. A blast wave propagates outwards and complex non-linear interactions occur when the blast wave reaches a service member. Blast from explosives has been studied for a long time. Recently, we have spent time studying the blast environment from burning propellant when service members operate weapon systems. The team looked at blast around operators during training with shoulder-fired weapons, mortars, artillery, .50 cal guns, and explosive breaching charges, to assist researchers studying whether multiple, sub-threshold exposures can cause negative outcomes.
2. What are blast injuries, and who is studying blast effects on the brain?
Wagner: When exposed to blast waves, service members may experience Traumatic Brain Injuries (TBI) and adverse brain health effects. Our service members are increasingly reporting physical, cognitive, and psychological symptoms, either after one large explosion or repeated low-level blast exposures over a career, that affect their quality of life. At ARA, researchers are working to increase understanding about the connection between blast exposure and brain health effects. This relationship is complex and is studied by multidisciplinary teams from government, academia, and industry with expertise in blast physics, biomechanics, physiology, neuroscience, and medicine.
3. What have we learned about the long- and short-term effects of blast and neurotrauma over the years?
Wagner: Most critically, we have identified a plausible correlation between blast exposure and chronic symptoms such as headaches, fatigue, and cognitive difficulties even without a TBI diagnosis. Many hypotheses have been investigated to explain how a shockwave interacts with the brain, resulting in these negative effects, without a clear answer. What we are seeing is that blast-induced TBI and its symptoms may be fundamentally different than concussions from head impacts.
4. Why have we seen increased concern related to blast effects over the last couple decades?
Wiri: Service member brain health concerns drive most of the work we have done recently. Many years ago, DARPA fielded small body-mounted blast sensors and collected data from combat. This was a big step forward because we had quantified data (“dose” measurements) on blast exposure levels. ARA helped analyze the data, and we learned a lot from this data. In the last few years, we have focused on blast exposure in training. These events are much lower magnitude blast exposures than what was typically seen in combat, but the concern was around low-level repeated blast exposure and possible effects on the brain.
5. What are some key milestones in ARA’s long history of blast research?
Wiri: ARA has long been a leader in blast research. ARA researchers actually collected body-mounted blast data during explosive breaching events back in 2006. This effort showed it was possible to collect blast data in the field. My involvement started with the DARPA blast sensor data analysis. One thing we learned from this effort and the DARPA Blast Gauge work was the need to provide standardized blast metrics from body-mounted blast sensor data. In cooperation with DoD customers, ARA developed FAST-CT software to process blast sensor data. FAST-CT uses physics-based algorithms to take complex blast data with shock reflection, diffraction, and shielding effects and output standardized blast metrics for each blast event.
Wagner: FAST-CT has decades of blast “know how” in the algorithms. But the two major things FAST-CT does is provide: 1) standardized blast metrics (incident peak overpressure and incident peak overpressure impulse) and 2) removal of false positive data. Standardization is important because when body-mounted sensors were first released, each research group (often medical researchers rather than people trained in blast physics) processed data in their own way. This made it challenging to compare results from different groups. In other words, we weren’t getting “apples-to-apples” comparisons. Second is removing false positives. Almost all sensors record data that is not from a blast event (false positives). In our experience, this is rare, but it is critical this data is removed prior to exporting to a service member medical record. Historically, identifying false positives was done by hand. That is just not practical if a large number of blast sensors are deployed. We addressed the issue by writing software to identify false positives.
6. What current solutions does ARA offer that can help expand our collective knowledge about blast effects, mitigate them, and improve treatment?
Wagner: Automation and standardization to process and analyze blast sensor data is critical. I believe software is the best way to address the “big data” problem with thousands or even tens of thousands of service members getting blast sensors to monitor blast exposure. Secondly, as a community we need to make progress on the “dose/response” relationship between blast exposure and brain health.
Wiri: One area I think is important to consider is training and education to mitigate blast exposure in training: getting “left of the boom.” Service members are smart and will take our research such as blast overpressure contours to reduce their exposure to blast. This can be minor changes to body position or stepping away from a blast source while still meeting training goals. As a team, we are dedicated to continuing our work to provide innovative solutions that further the body of knowledge surrounding brain health and protect the Warfighter from the potentially insidious effects of blast.
