LDA linear danger area LO low temperature (weather) LOA limit of advance LOGSTAT logistical status LP listening post LZ landing zone material factor the strength, hardness, and mass of the material to be demolished mb millibar (a metric unit used to measure air pressure) MDI modernized demolition initiator ME main effort mechanical belay a belay that uses mechanical devices to help the belayer control the rope, as in rappelling MEDEVAC medical evacuation METL mission-essential task list METT-TC mission, enemy, terrain (and weather), troops (and support) available, time available, and civil considerations Middle– of–the–Rope Clove Hitch knot that secures the middle of a rope to an anchor Middle-of-the-Rope Prusik knot that attaches a movable rope to a fixed rope, anywhere along the length of the fixed rope; see also End-of–the–Rope Prusik MG machine gunner MOPP mission-oriented protective posture MR moonrise MRE meal, ready to eat MS moonset MSD minimum safe distance MSL mean sea level Munter hitch commonly used belay that requires little equipment NATO North Atlantic Treaty Organization NAV navigation NFA no-fire area NLT no later than NVD night-vision device NVS night vision system OAKOC observation and fields of fire, avenues of approach, key terrain, observation, and cover and concealment OBJ objective occlusive dressing a dressing that seals a wound from air or bacteria OD olive drab OOM order of movement OP observation post