Colvard MD, Naiman M, Danziger L, Hanley L. Handheld directed energy sensor for environmental monitoring and clinician safety. Aviat Space Environ Med 2010; 81:602–4. Introduction: Directed energy (DE) research and development is generating more powerful portable devices designed to support operational, environmental, clinical, point detection, and remote-sensing applications. These same DE devices present potential for injury, thereby impacting medical operations. The environmental surveillance and clinical communities require handheld sensor platforms that afford preemptive detection and monitoring of potentially hazardous exposures to DE and other electromagnetic (EM) frequencies. Methods: A personal digital assistant (PDA) was interfaced with a wavelength sensor board via a multifunction data acquisition card to passively detect wavelengths in the 480–950 nm range. A 9V DC battery coupled to a voltage up-converter with a manual ON/OFF switch powered the sensor board. The sensor board was integrated with a standard operating system-based PDA. Graphical programming software integrated the data acquisition card with the PDA. Results: The DE wavelength sensor/PDA platform detected and relayed laser radiation information from 480 to 950 nm ranges, with graphical data output to the PDA screen. Discussion: This project demonstrated the technical ability to detect anthropogenic DE frequency signatures using a handheld, battery-driven DE sensor platform. Laboratory and field assessment studies are underway to validate operational applications. This DE-sensing prototype is designed explicitly for DE medical measurement and signatures intelligence (MED MASINT) to meet the protection needs of environmental and clinical operators.