By James Coomarasamy
BBC News, Arlington, Virginia
Capt Nuneville speaking "plain language"
Captain Michelle Nuneville has a lot of un-learning to do.
After many years on the force the commander of the Arlington police department's operations division is adjusting to life after the 10-codes.
Since they were first introduced in the 1930s, abbreviations such as 10-4 and 10-20 have been the natural language of the American cop; part of police folklore.
But, in Virginia they have decided that it is over and out for the 10-codes.
On a drive through the streets of Arlington, Capt Nuneville explained that the problem was a lack of compatibility.
Individual counties have their own 10-codes, and while some are common to all police forces, many are not.
As a car skidded to a halt next to us - narrowly avoiding a pedestrian - she was able to give a concrete example.
"If there had been an accident," she said, "I would have called in a 10-50, a 10-50i if the pedestrian had been injured. A 10-50f, if there'd been a fatality.
"Now, I happen to known that in neighbouring Montgomery County, a 10-50 means 'officer in trouble'."
The codes were originally introduced in order to keep conversations brief on a single police radio channel - and have gone on to have a long and distinguished career.
But the experience of Capt Nuneville and her colleagues on 11 September 2001 has proved to be the catalyst for their demise - in Virginia, at least.
When the plane hit the Pentagon that morning, the Arlington force found themselves co-ordinating rescue efforts, with the help of colleagues from neighbouring counties, who had offered their services.
But the contradictory 10-codes complicated an already-confused situation, convincing the state authorities that it was time for a change.
In 2003, Chris Essid was appointed Virginia's first inter-operability co-ordinator - the official in charge of improving the state's emergency communications.
He is the driving force behind the new linguistic regime.
"Just because your radio can talk to mine," he said, "if you're speaking Japanese and I'm speaking Chinese we won't understand each other. That's what you can get with the codes. And that's no good in an emergency situation."
The Virginia experiment is being watched very closely in neighbouring states - where not everyone is convinced that the codes can be jettisoned.
In Calvert County, Maryland, Assistant Sheriff Maj Thomas Hejl says it is not about folklore or nostalgia, but about practicality.
Brevity on the airwaves is still preferable, he argues, when mere seconds could save a life, and the codes help to ground an officer in his job.
"When you come out and go to work you give a 10-8," he explained. "It tells us you're on duty. It's a world in and of itself, which lets the rest of us know what's going on.
"If you don't know the 10-codes and aren't using them, you're not doing what the public expects."
The process of change will be gradual.
In Arlington, Capt Nuneville admits that it will be hard for officers - especially those who have been using the codes for many years - to adjust. She also says there will have to be new guidelines.
"In one county officers took to saying okey dokey, rather than OK - and that's just not professional," she said.
And as we listened to the voices on her radio, it was clear that many dispatchers and officers are still using the old system.
Although not to the extent that I thought. When I heard the dispatcher refer to a 10-18 and 10-37, I asked Capt Nuneville what they meant.
"1018 is the number of the house, she said. And 10.37? Look at your watch. It's the time."