You're rushing to or from work or the store. The road is wide and straight. You're going 40 mph through a residential area, even though the speed limit is 25.
Maybe you don't realize you've got a lead foot.
More importantly, maybe you don't realize that by driving even a little faster you greatly increase the possibility that your car could strike a child.
Harford County is trying to alert drivers who may be speeding in residential areas such as Glenwood Estates, a community that has many children.
Traffic officials recently set up a "radar-activated speed-notification board" in the neighborhood. Linked to a radar gun, the unit flashes motorists' speeds on a lighted board as they drive by.
The officials chose East Ring Factory Road, which connects Md. 22 and Md. 924. People use it to bypass Bel Air.
Shortly before the speed board was used, drivers were traveling an average of 34 mph in a 25 mph zone, said Jeff Stratmeyer, chief of the county's traffic operations section. Some have been clocked much higher.
When officials returned Wednesday with a radar gun to see if people had slowed down, drivers were traveling an average of 31 mph on East Ring Factory Road.
"I've noticed a difference," said Stratmeyer, who uses the road himself. "We're just trying this as an experiment to see if it helps."
So far, Harford County is trying to get the attention of drivers but is not issuing tickets.
The speed board is on loan from Baltimore County traffic officials. Stratmeyer wants Harford County to buy one at a cost of about $1,800, so he can routinely target problem streets where commuters and others regularly speed through residential areas.
Getting people to slow down is no easy task, Stratmeyer said, but the price of not doing so could be a child's life.
If people slow down, he said, "they're losing less than a minute of their time and drastically reducing the risk to children and themselves." To make his point, he said it takes only 53 seconds longer to cover one mile when traveling at 25 mph instead of 40 mph.
Dr. Joseph Wiley, a pediatric oncologist at Johns Hopkins Hospital, lives in Glenwood Estates and has a 2-year-old child. He and his neighbors have been working with the county to try to get drivers to slow down.
He said studies have shown that a driver traveling 32 mph rather than 25 mph increases by six times the risk of fatally injuring a child who is a pedestrian.
Both the child and the driver have less time to react, Wiley said, and the impact from the car is much greater the faster a driver goes.
Wiley said he is encouraged by the county's efforts to lower speeds in his neighborhood and others. The speed boards may have a temporary effect, he said, "but it's hard to know what the long-term impact is going to be."
Baltimore County has two speed boards it has used regularly during the past five years. It's one of the few jurisdictions in Maryland to use them, said Richard Moore, chief of the county's Bureau of Traffic Engineering.
"It's purely educational," he said. Many drivers don't want to be breaking the law, he contended. Some are surprised when the board shows them how fast they are traveling.
People even drive fast in their own neighborhoods, Moore said. According to data the county has compiled, more than 50 percent of the speeders live within a mile of the radar unit, he said.
Moore said Baltimore County sometimes uses the board in conjunction with police radar. Drivers are warned with the board at one point, then a short distance later, a police officer clocks their speed again. If they haven't slowed down, they get a ticket.