The most increased (highest) force protection level for a military base or installation is Force Protection Condition Delta , commonly written as FPCON DELTA.

What FPCON DELTA means

  • FPCON DELTA is the top‑tier force‑protection condition used by the U.S. military and allied forces.
  • It is applied when a terrorist attack has occurred or is considered imminent in or very near the installation, triggering the strictest possible security measures.

How it compares to other levels

Force‑protection conditions are usually ordered like this, from lowest to highest:

FPCON level| When it applies
---|---
NORMAL| Routine, peacetime conditions; baseline security. 3
ALPHA| General, low‑level threat; minor tightening of procedures. 35
BRAVO| Increased, more predictable threat; more checks and barriers. 35
CHARLIE| Incident occurred or intelligence indicates an imminent attack; heightened alert and access controls. 35
DELTA| Attack happening or deemed inevitable ; maximum security, possible lockdowns, and all available measures deployed. 13

Why DELTA is “most increased”

  • At FPCON DELTA, installations often restrict movement, increase patrols, harden perimeters, and may suspend non‑essential activities to protect personnel and critical assets.
  • Commanders can raise their local FPCON above the regional minimum (for example, USNORTHCOM‑set levels), but DELTA remains the ceiling for standard force‑protection conditions.

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