A bill that requires employers in California to provide at least three days of paid sick leave a year to their workers was signed into law Wednesday by Gov. Jerry Brown, a decision cheered by labor unions and workers on modest incomes, but opposed by business groups concerned about rising costs.

"There have been a lot of times that I have had to decide between wealth and health," said Dominic Ware, a Hayward resident who works in the retail industry. "I had to decide between coming into work or staying home because I was sick. This law will create a standardized system."

Labor groups said the legislation would help an estimated 6.5 million workers in California who cannot take a paid sick day when they are ill or a family member is sick. Business groups raised fears that the legislation would increase their costs of doing business and reduce their flexibility to schedule employees. California became the second state in the nation, after Connecticut, to adopt a paid sick leave law.

"Whether you're a dishwasher in San Diego or a store clerk in Oakland, this bill frees you of having to choose between your family's health and your job," Brown said in a prepared release. "California is putting its workers first."

Employers are mandated to provide sick pay for an employee who works 30 or more days in a single calendar year, under the measure, AB1522. Employees will earn a minimum of one hour of paid sick leave for every 30 hours worked. The bill, authored by Assemblywoman Lorena Gonzalez, D-San Diego, is scheduled to go into effect in July 2015.

"As a single working mom, I know firsthand the challenge of having to juggle a sick child who needs to see a doctor and your responsibilities at work," Gonzalez said.

The legislation is likely to benefit the 40 percent of California's workforce that does not have access to paid sick leave, supporters of the measure said.

"The people who are most affected by a lack of paid sick leave are those at the lower end of the wage spectrum," said Ben Field, executive officer with the South Bay Labor Council. "For these lower-income workers, it's not just the loss of the pay. They are barely getting by, and it could be a choice of paying rent or putting food on the table."

Plus, workers could be more productive by taking time off to improve their health than if they attempted to gut it out at work while feeling ill, Field said.

Business groups complained that the law would impose additional costs on companies as well as erase flexibility in scheduling for industries that need it the most.

"The nature of our industry allows for flexible scheduling and shift swapping that won't adversely affect an employee who comes down sick," said Jot Condie, president of the California Restaurant Association. "A one-size-fits-all approach to sick leave is inappropriate and onerous."

Dining establishments represent an industry that is unique compared to others, said Angelica Pappas, a spokeswoman for the restaurant association.

"A lot of times, the restaurant has people on call when somebody calls in sick," Pappas said. "It is really common to bring in an extra body when somebody is ill. With this legislation, the restaurant will often have to pay twice. Once for the paid sick leave, and once for the employee who comes in to cover the shift."

Yet the experience of some municipalities suggests that employers will be able to cope with the effects of the law, said Ken Jacobs, chair of the UC Berkeley Labor Center.

"Employers were very worried in San Francisco going into the enactment of a paid sick leave measure in that city," Jacobs said. "The employers found that it was not a difficult process. And for the employees, it was a big deal. This gives low-income people a chance to stabilize employment."

Labor leaders want to see further improvements to the law.

"A maximum of three days off is not enough," Field said. "And the bill does not cover all the workers that it should. Home care workers were exempted at the last minute from the bill."

Contact George Avalos at 408-859-5167. Follow him at Twitter.com/georgeavalos.