By Mike Leidemann
Advertiser Transportation Writer

Sometimes the debate over Hawai'i's speed limits sounds like one of those TV commercials for long-distance telephone service: "A dollar? What can you get for a dollar?"

Let's put it this way. "One second? What difference can that make?"

Actually, like the commercial says, a dollar is worth quite a bit. And when it comes to traffic safety, one second often means the difference between life and death.

Most people have an average of about three seconds to avoid a traffic accident, according to nationwide statistics. If drivers had just one more second to respond before they hit something, they often could avoid a collision.

One second? How can one second make such difference?

Consider this: At 35 mph, a vehicle travels about 51 feet every second. At 45 mph, the same vehicle goes 66 feet in a second. At 55 mph, it's 80.6 feet. At 65 mph, it's 95.3 feet. At 75 mph, a vehicle is traveling 110 feet every second.

"At 70 miles per hour, you can go off the road and slam into a guardrail in less than half a second," said Frederic Mottola, a traffic safety consultant who was in Honolulu a few months ago, just before the state launched its new traffic camera enforcement program and touched off a statewide debate on the value of speed limits.

Or to put it another way: "During the one-and-a-half seconds you need to glance at your speedometer, you'd have traveled about 150 feet at 60 miles per hour."

One of Mottola's missions in life is to get drivers to understand the four-second rule. That means drivers should always be thinking four seconds ahead of themselves, keeping an eye on what's happening with traffic, the road or other distractions four seconds down the road.

"Drivers need to start thinking in terms of seconds, instead of car lengths or anything else," Mottola said.

To do that, Mottola suggests practicing driving in four-second blocks. Pick a spot on the road and take a guess how long it will take you to reach it. Then count off four seconds and see how close you come to the spot.

Of course, those four seconds involve a lot more distance when you're doing 70 mph instead of 35 mph. At 35 mph, it actually can take longer than you think to reach that telephone pole or traffic sign you've picked out. At 70 mph it gets there a lot quicker than you expected.

Once they get the hang of it, drivers usually become much better at avoiding accidents when they follow the four-second rule, Mottola said. They start to appreciate how much difference there is between a reasonable speed and an excessive one.

In other words, they start to realize just how valuable one second can be.

Mike Leidemann's Drive Time column appears every Tuesday. Reach him at mleidemann@honoluluadvertiser.com or 525-5460.