COWAC curated content on Blast Overpressure Science & Legislation

By Timothy J. Grossman, President

Coverage window: September 14–21, 2026

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This Week At a Glance

The big item this week is a large VA-cohort study in Neurology (published Sept 16) linking high-level blast exposure to significantly elevated long-term risk of seizures, neuropathy, and stroke, plus a cluster of systemic conditions (hepatitis, diabetes, high cholesterol, chronic bronchitis/emphysema), reinforcing that blast exposure is a whole-body issue, not just neurological.

A companion biomechanics paper (Shock Waves, also Sept 16) measured intracranial strains at breacher-level blast exposure stayed well below established injury thresholds, suggesting strain alone may not explain breacher injuries and pointing researchers toward cavitation as an alternative mechanism. On the policy side, no new bills, hearings, or agency actions specific to blast overpressure were found this week; the standing item we track, H.R. 9237 (Take Care of America’s Veterans Act), remains stalled with no new floor action since July.

Science & Research

– Large VA cohort study finds blast-exposed veterans face substantially higher long-term disease risk. In a study of 36,641 VA-enrolled veterans followed up to 10 years post-service, high-level blast exposure was associated with a 79% higher likelihood of seizure diagnosis, 38% higher likelihood of neuropathy, and 35% higher likelihood of stroke, along with elevated rates of hepatitis B/C, diabetes, high cholesterol, and chronic bronchitis/emphysema. Published in Neurology (American Academy of Neurology), Sept 16, 2026; led by Sarah L. Martindale, PhD (Salisbury VA Health Care System).
Source: Martindale, S. L., et al. (2026). Linking Military Blast Exposure to Veterans Health Administration Diagnoses. Neurology. DOI: 10.1212/wnl.0000000000218595. https://www.neurology.org/doi/10.1212/WNL.0000000000218595

– New biomechanics data complicates the “strain injury” theory for breachers. Using an instrumented surrogate headform exposed to breacher-representative blast conditions (~75 kPa, 5 ms duration), researchers measured intracranial strains consistently below 0.5%, well under thresholds associated with long-term potentiation (3.7–6.7%) or axonal injury (5–10%). The authors argue this points away from strain as the primary injury driver at breacher exposure levels and toward cavitation effects as a mechanism worth investigating instead.
Source: https://link.springer.com/article/10.1007/s00193-026-01272-6

Notably, a May 2026 Journal of Defense Modeling and Simulation study found that standard empirical formulas significantly underestimate peak overpressure in door-breaching scenarios and proposed a faster method for estimating safe standoff distances being cited in current breacher-safety discussions.
Source: https://journals.sagepub.com/doi/10.1177/20414196261443542

Legislation & Policy

H.R. 9237, “Take Care of America’s Veterans Act” (TCAVA): no status change this week. The bill remains stalled since a motion to recommit failed by one vote (210-211) on July 16, 2026, after which further proceedings were postponed; no new floor action, committee markup, or Senate movement has occurred since. We support Section 311 (establishes a VA Blast Overpressure Task Force) and Section 310 (Precision Medicine for Veterans Initiative modification / suicide reporting), and oppose Section 108 (restructures VA disability ratings for tinnitus and obstructive sleep apnea, used partly as a ~$57B budgetary offset). We’ll keep flagging this item every week and will call out immediately if 310/311 or 108 are amended, stripped, or split into separate legislation.
Source: https://www.google.com/url?q=https://www.congress.gov/bill/119th-congress/house-bill/9237&source=gmail&ust=1790039003154000&sa=E

No new legislative or regulatory action specific to blast overpressure standards was identified this week. The separate Blast Overpressure Research and Mitigation Task Force Act (H.R. 6444, sponsored by Rep. Ronny Jackson; companion S. 4777) remains pending with no floor votes or new hearings since its House VA Committee legislative hearing in April 2026.
Source: https://www.congress.gov/bill/119th-congress/house-bill/6444&source=gmail&ust=1790039003154000&sa=E

Also, no new OSHA rulemaking, DoD policy memos, or state legislative activity on blast overpressure exposure standards were found in the past 7 days. The most recent substantive DoD policy action remains the August 2024 Deputy Secretary of Defense memo mandating 12 blast-overpressure mitigation actions, and the most recent oversight development is GAO’s August 18, 2026 report finding DoD’s brain-health monitoring rollout is hampered by staffing and technology shortfalls (GAO-26-107829).