Changes earmarked for Florida's joint underwriting association for high-risk workers compensation businesses brought outcries from industry groups this week.

Gov. Lawton Chiles' is seeking a 20 percent cut in employers' premiums. House-Senate workers' compensation conferees said Tuesday the Legislature was still reviewing the bill in a special session.Rather than assess insurers to subsidize deficits in the high-risk pool, the panel voted for a pool with premiums high enough to make compensation coverage available to occupations that can't get insurance on the open market, such as roofers and steelworkers.

Lawmakers also expanded the joint underwriting association to include businesses large enough to operate their own workers compensation plans.

The conference committee bill sets up three classes of insureds, said Dan Sumner of the Florida Department of Insurance.

High-risk businesses - as well as small business paying annual premiums of $2,500 or less with two years of clean claims records - each would pay higher premiums but would not be assessed for risk-pool deficits.

But "for whatever reason, the law is silent" on whether self-insured companies would be assessed in the case of a deficit, Mr. Sumner said.

Businesses want some assurance that the JUA will continue to be self- sustaining. Four hundred self-insured companies such as Publix, Winn-Dixie and many utilities cover their own risks and had previously been exempt from assessments for the high-risk pool.

Many large businesses "have just come unglued" over the changes, and ''that alone could kill the bill," said Jon Shebel, president of Associated Industries of Florida.

Lawmakers had been scheduled to finish a $40,000-a-day special session last Friday, but Gov. Chiles extended it through today for more work on workers compensation.

Gov. Chiles said he wouldn't guarantee lawmakers would go home today.

He had said Friday that his analysts estimated the bill would bring only a 16 percent drop in employers' premiums for the mandatory coverage of on-the- job injuries.

Gov. Chiles said if the bill didn't put tougher controls on health-care and court costs and cut compensation rates 20 percent, "That's not a good bill."

The National Council of Compensation Insurers, said the bill would cut rates 13.6 percent to 17.5 percent in the first year and ultimately bring a 14 percent to 22 percent reduction, according to Sen. Toni Jennings, R-Orlando.

The group added a 10 percent credit Monday for employers who send injured workers for treatment under managed-care plans, and provided that managed-care

plans become mandatory after three years.

That would result in an average 24 percent premium decrease, said Sen. Jennings.