A few months ago, I blogged about “plain speak” and how terminology changes from place to place. Now that I'm working in the Western US, I've learned a NEW term for an ambulance – out here, it's called a “Rescue”. They have “Heavy Rescue” or “Technical Rescue” units – those are the “rescue” trucks I'm used to talking about.
Anyway – the agency I work for still uses some 10-codes. Things like “give me a 21”, short for 10-21, meaning: call dispatch via phone. Some folks use 10-7/10-8 for out of service/in service, and there's a smattering of other ones, too. There's a new one for me, “Code 4”. It's actually the same as a 10-code I'm used to from the police back home, “10-92”. Code 4, 10-92, or even “92” mean the same thing, ostensibly, “status OK”. That said, the code means so much more than that. The use is very context-dependent. Most often, it's how I answer status checks by dispatch when my unit hasn't been on the air recently.
We also use it for other things. Talking about a disabled motorist: “He's code 4, waiting for AAA.” Or, after a property damage collision, “occupants are all Code 4, just want to file a report.”
An example, from an EMS perspective, is a call I had at the University EMS service, while I was a supervisory lieutenant. I was onscene for a psychiatric emergency, and the other lieutenant arrived, and asked me on our ops channel if I needed anything. My response was “Nope, we're 92 in here, just let me know when the BLS arrives.” Suddenly, by using that 10-code, he knew that a University police officer and myself weren't doing anything useful inside, and were simply waiting for the ambulance to arrive, so the person could go to the hospital for care, after their cry for help.
Another great use from the EMS side is when we are requesting a LE unit to assist us for something minor – forcing access into a house, dealing with securing property, that sort of thing. Over the years, when I've request a LE unit for something minor, it's not uncommon to get more than one, because they all come, just in case I'm in trouble. It's great to know the cavalry will come when I call, but it's also a waste of resources. Being able to use a code that the dispatcher and LE know, that says “I'm OK” can help ensure that my LE friends don't get hurt racing to “assist EMS” for something dumb.
“Code 4” isn't some huge secret. It's online, and can be heard on most scanner apps for western LE agencies. Its use is varied, and very flexible. It, and 10-92, the 10-code from back home, are one of the more useful LE “codes” that I've used.