It's getting dark, you're running late and you're coming up fast on a railroad crossing. You may not know it, but you are about to enter . . . The Conspicuity Zone.

That's transportation-industry language, and it has to do with making train locomotives more visible, or conspicuous, so fewer cars drive in front of them and get crunched.The Federal Railroad Administration has proposed rules to make trains easier to see from a distance by requiring three headlights in front, instead of one.

That should give motorists up to 20 percent more time to react and stay out of a train's way, the government believes.

But don't rest too easy. The Conspicuity Zone is dangerous.

More than 600 people died in collisions at railroad crossings last year. Nearly 2,000 more were injured in a total of 4,979 accidents. While those numbers may seem high, they are about half of the level of carnage 20 years ago at crossings.

The FRA's top safety officer, Grady Cothen, sees an enormous pay back from the new rules in the form of fewer accidents.

Though the program would cost railroads $5 million a year over 20 years, Mr. Cothen said, avoiding just 11 accidents annually would result in an overall savings.

If the FRA's estimates are correct, the annual benefits would be 300 fewer accidents, 75 lives saved and $120 million less in legal and other costs.

There are a couple of other minor details you should be aware of.

* Those headlights would only be needed if the train travels at more than 20 mph.

* Freight cars, which make up about 95 percent of the length of a train, aren't required to have lights or any other markings, and as a result you can't see them well at night.

Just one more thing before you leave the zone.

If you're like many motorists, you may wonder why there isn't an overpass that makes train-vehicle crashes impossible.

Relax. It's only a matter of money.

The General Accounting Office estimates that it costs $3 million to build a single overpass.

Look at it this way. You can either wait a few minutes or pay more tax.

And one final warning.

Slow down before you enter The Conspicuity Zone.

If you think you can survive a race with 10,000 tons of metal, you are wrong. Dead wrong in the Conspicuity Zone.