12-89. The G-3 (S-3) briefs friendly maneuver unit dispositions, including security forces, as they are arrayed at the start of the operation. Subordinate commanders and other staff officers brief their unit positions at the starting time and any particular points of emphasis. For example, the chemical, biological, radiological, and nuclear (CBRN) officer states the mission-oriented protective posture level, and the chief of fires (fire support officer) or fires unit commander states the range of friendly and enemy artillery. Other participants place markers for friendly forces, including adjacent units, at the positions they will occupy at the start of the operation. As participants place markers, they state their task and purpose, task organization, and strength.