COLUMBIA - South Carolina, which has the worst alcohol-related traffic death rate in the nation, is about to take another step toward bringing its historically weak DUI laws in line with a majority of other states.

A spokesman for Gov. Mark Sanford said the governor will sign a bill making it illegal to drive with an alcohol concentration measured at 0.08 -- the equivalent, for a 170-pound man, of drinking four beers in an hour's time. The current law lets people drive with a concentration of up to 0.10.

If Sanford signs the bill by Friday, the new law will go into effect at noon on Aug. 19. If not, it becomes effective two months after he signs it. The fine for a first offense will increase by $100, to $400. The six months' license suspension remains the same.

Still, experts say S.C. laws against drunk driving will continue to lag behind in an area that they say is also a key component in making highways safer. Forty states, including North Carolina, suspend licenses on the spot when a driver's blood-alcohol level exceeds the legal limit. South Carolina still does not.

In fact, when the S.C. Senate passed the 0.08 standard this year, it voted at the same time to repeal the state's existing license suspension rule. That law applies only if a driver's alcohol concentration is 0.15 or higher, or if the driver is younger than 21. House members, however, insisted on keeping the suspension law intact, and it remains on the books.

But the law may be not be strict enough to keep South Carolina in compliance with federal rules. As much as $60 million in federal highway money is at stake.

Congress passed a law in 1998 requiring states to adopt the 0.08 legal limit by Oct. 1, 2003, to be eligible for a pot of highway construction aid. The law said states must apply the 0.08 standard to their automatic license suspension policies, as well.

S.C. highway safety director Max Young said last week that he is querying federal authorities, "asking them to tell us if, in fact, this law meets their requirements."

Sen. Wes Hayes, R-Rock Hill, said that considering the historic reluctance of S.C. lawmakers to pass tough anti-DUI laws, he doubts that the 0.08 legal limit would have passed this year were federal dollars not tied to it.

"I hate to say it, but sometimes that's the incentive that it takes for us to do what needs to be done," said Hayes, who has fought for numerous highway safety measures during his 18 years in the legislature.

South Carolina was one of the last states to make it illegal to drive with an alcohol concentration measured at or above an established level. The legislature passed the 0.10 standard in 2000. Before then, someone charged with DUI could argue in court that he wasn't impaired, even though his blood alcohol level was 0.10 or higher.

The state's hands-off approach to highway laws manifests itself in other ways. South Carolina still does not allow law enforcement officers to pull over drivers for failing to wear seat belts.

S.C. lawmakers' longstanding opposition to stronger DUI laws is deeply rooted in the state's rural, conservative traditions. There is a reluctance to interfere with personal freedoms and resentment of federal mandates.

When the Senate in 2000 passed the law making a 0.10 blood-alcohol level automatic proof of driving under the influence, it did so over the strenuous objections of veteran Sen. Glenn McConnell, R-Charleston. "This is a deliberate attack on your basic right to be presumed innocent until proven guilty," he said during a filibuster against the bill.

Referring to the new 0.08 law, Hayes said he considers the new standard an important step.

"The national highway safety people strongly believe that it makes a very positive difference; that's a reason a lot of the highway construction dollars were tied to it," he said.

Young said that research done nationally shows that 0.08 is the true level at which people's reactions and coordination are impaired by alcohol.

Whether South Carolina's rate of people who died in collisions where alcohol was the primary cause -- 156 deaths in 2001, 56 percent of all S.C. highway fatalities -- will decline because of the new law remains to be seen, Young said.

But, he said, "I truly believe that it's going to bring great improvements."

Young said South Carolina's DUI laws are still confusing and riddled with loopholes and ambiguities. "I think the law and the way it's written has a great deal to do with the problem that we have," he said.