The Joint Service Member Occupational Health Assessments (JSOHA) process is an enduring mission that complements the pre-materiel fielding Health Hazard Assessment process by providing procedures to capture, measure, and record potential health risks associated with potential and actual Service member exposure to fielded materiel systems. The quantitative data collected by the JSOHA team are used to identify potential health outcomes associated with exposure and will populate Service members’ medical records as one component of the Individual Longitudinal Exposure Record via the Defense Occupational and Environmental Health Readiness System – Industrial Hygiene. The objective of this poster is to give an overview of the Tier 1 Weapons Systems sampling results obtained from Fiscal Year 2018 National Defense Authorization Act Section 734 Blast Overpressure Study, Line of Inquiry 3: Exposure Environment JSOHA. The JSOHA process is codified as a post-fielding evaluation in Army Regulation 40-10, Health Hazard Assessment Program in Support of the Army Acquisition Process. Sampling is based on Department of Defense (DoD) Industrial Hygiene Exposure Assessment Process (DoD Instruction 6055.05) utilizing Similar Exposure Groups. Personal samples obtained were comprehensive in nature and included blast overpressure, impulse and/or steady-state noise, and chemical combustion products. The JSOHA team sampled at least one use-scenario and condition (e.g., posture, type of round, elevation) for all 15 Tier 1 Weapons Systems and Breaching Charges as defined by the Section 734 Working Group and continues to search for new opportunities to baseline other conditions of fire. Risk levels for the use-scenarios and for each occupational hazard will be presented in the poster. The Defense Health Agency Public Health JSOHA Team has the mission and means to assess Service member exposure to health hazards resultant of operating weapon systems and breaching charges. The JSOHA process provides Commanders and other risk managers with a comprehensive assessment of Service members’ exposures to potential occupational hazards inherent to using military equipment during training and combat. The end state is reduction or elimination of disease and non-battle injuries through proper identification of Service member occupational exposures and the development and implementation of appropriate industrial hygiene controls or mitigation strategies.