The Senate recently approved legislation that would extend unpaid leave for wounded military personnel from the 12 weeks allowed under current law to six months. But corporate advocates are more concerned about another measure that would require companies with 15 or more employees to provide seven paid sick days annually for people who work at least 20 hours each week.

One reason business groups don’t like the paid sick leave bill is because the seven days would be added to the companies’ existing paid-time-off benefits unless the leave was specifically designated as sick time.

The bill would also prohibit employers from changing their leave policies between the time it is enacted and the time it becomes effective.

Advocates of the bill say that the relationship between paid-time-off and paid sick days has yet to be worked out because there are so many variations in company PTO programs. Others say that paid sick days will reduce costs for employers. Vicky Lovell, director of employment and work/life programs at the Institute for Women’s Policy Research says that companies will save about $8 billion annually by reducing turnover, increasing productivity and halting the spread of the flu in the workplace.

The program would mostly benefit low-income and minority workers, many of whom are in the hospitality and food service industries.

Currently, about 52% of private sector employees receive paid sick days.