Signal 4 Police Code Meaning & Definition

What Does Signal 4 Mean?

Signal 4 is a police radio code most commonly used to mean Carbon Monoxide.

Police departments and dispatch centers may use Signal 4 differently, but Carbon Monoxide is the most common meaning found in our database of agencies across the United States.

Most Common Meaning: Carbon Monoxide

Used this way by: 50% of agencies on this page
Used in: 2 agencies across 2 states
Category: Emergency
Consensus: MediumMost agencies use this code similarly, but some regional or agency variations exist.

Code Distribution Breakdown

Carbon Monoxide: 50% (1 agency)
Investigate (Fire, Burning, Smoke, etc.): 50% (1 agency)

Signal 4 Police Code Meanings by Agency

2 agencies across 2 states
Signal 4: Carbon Monoxide
CategoryEmergency
State Georgia
Agency Atlanta Police Department
Sources
Signal 4: Investigate (Fire, Burning, Smoke, etc.)
CategoryIncident
State Ohio
Agency Cincinnati Police Department
Sources

Why Does Signal 4 Have Different Meanings?

Police radio codes are not standardized nationwide. Different agencies may assign different meanings to Signal 4 , which is why multiple definitions can exist for the same code.

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