Butler County officials issued a reminder Friday that a new 1/4-cent sales tax is now in effect.
The tax, which took effect April 1, will be used to upgrade the county's emergency communication radio system.
Voters approved the increase in November.
The $12.9 million upgrade, which is scheduled to be completed by October 2012, will increase radio coverage to 95 percent of the county.
The tax will expire in 10 years unless the improvements are paid off earlier.