No more 10-4 for Maryland State Police

There’ll be no more 10-4 in Maryland State Police radio communications.

The agency abolished the numerical codes as of Feb. 1 in favor of plain English. Police said the change is meant to reduce confusion, especially during incidents involving more than one police or emergency agency.


So, now, instead of ending their shifts by announcing that they’re 10-42, state troopers will presumably just say they’re off duty. 

The Associated Public Safety Communications Officers list 100 different “10-codes.” They include 10-89 for a bomb threat, and 10-45 for an animal carcass.