Kenny Martinez turns the ignition switch and waits a few seconds for the LifeSaver interlock on his company truck to warm up. When the machine indicates it's ready, Martinez emits a low, warbly hum into a tube.

The device reads his breath-alcohol content and, confirming that he is sober, allows him to start the truck.

But about five minutes later, the device asks for another test. Martinez picks up the tube and makes the same humming noise.

Periodically during his journey, he'll be asked to blow again, and again, in an unpredictable pattern. If he fails to do so, the machine will prompt him with additional beeps. Eventually his horn will sound and his lights will flash, indicating he has only a couple of minutes to pull to the side of the road before the vehicle will shut down.

While Martinez cruises the streets near Santa Fe Community College, the device beeps from time to time, reminding him that he is due to take his vehicle to L.A. Interlock for servicing.

At that time, information on each and every "blow" during the previous month will be downloaded. Data showing the times and results of each "blow" will be forwarded to his probation office.

Martinez, a five-time offender, has had three ignition interlocks. But since his fifth conviction, he's been sober, and the device has been helping. A year from now, he will be allowed to remove it and get an unrestricted license, he says.

A construction superintendent, Martinez is one of thousands of New Mexicans who have court-ordered ignition interlocks in their vehicles.

Some users complain the device is a distraction. But others say it's no more a diversion than talking on a cell phone.

Martinez is an old hand. In the past, he admits, "It was a hassle because I was drinking." But now, he says, "I don't have to worry, 'Do I still have alcohol in my system?' "

The BAC programmed into the device is usually set well below the legal limit of 0.08 at about 0.025, so a driver could have a small amount of alcohol and get his car to start.

Although Martinez often tells his story to convicted drunken drivers at DWI Impact panels, having an ignition interlock is still somewhat embarrassing, he admits. "There are times when I'm dealing with a client. They walk up to the truck and stand there while I'm getting ready to leave. I'm hoping they'll walk away so they don't see me blow."

Martinez says he wishes he had gotten sober 20 years ago. "As sweet as life is going for me now, I keep thinking I should have done this a long time ago. I would have saved myself a year and a half of prison time."

His first DWI was in 1989, Martinez says, but all he got was a fine. Punishment for the second wasn't much harsher. But after the third conviction, the court ordered him to install an interlock. And after the fourth, he was sentenced to a year in a half in prison. After getting out, he continued to drive on a revoked license.

The turning point for Martinez came after his fifth arrest in 2005. This time he was facing three years in prison. While awaiting trial, he decided he'd had enough. He moved into Juan's Sober House, wore an ankle bracelet, monitored his BAC, attended AA and studied the Bible. By the time he got to court, Judge Steven Pfeffer agreed to take a chance on him and sentenced Martinez to five years' probation, a hefty fine and an ignition interlock.

Ignition interlocks are usually most effective with casual drinkers willing to accept responsibility and take their punishment because "they want to get over with it," Martinez says. Chronic drunks, on the other hand, "try to get around (the law) and end up getting caught again and staying in the system like I did," he says.

Today he is happy to talk to all kinds of DWI offenders at victim impact panels because of "where I am today. I'm proof a person can change."

Contact Anne Constable at 986-3022 or aconstable@sfnewmexican.com.