Massachusetts may soon become the third state to require employers to pay their workers for taking time off while sick. A statewide ballot measure in November would give one hour of sick time for every 30 hours worked, with an upward limit of 40 hours for the year.

The proposed law would require employers with more than 10 full-time employees to pay for sick time. For smaller businesses, workers would have the right to take time off while sick but wouldn’t collect payment. The measure would protect workers who take their earned time off from retaliation by employers.

“This is a small, but very significant step in the [economic] recovery that has missed a lot folks,” said Ellen Bravo, executive director at Family Values at Work, a national group advocating for paid sick days this year. Bravo noted that several states are also considering mandatory increases to their minimum wage laws this year, another national effort pitched as a boost to low-wage workers.

“We certainly see them as going hand-in-hand,” she said. “Paid sick time is really about not being docked your pay. If I make a great wage, but I lose it because my kid gets sick, I’m not in great shape.”

At least eight cities already have some kind of paid-sick-leave ordinance, including San Francisco, Seattle and Jersey City, N.J. Oakland, Calif., also has a ballot measure dealing with sick leave in November. Connecticut was the only state to have a law until California Gov. Jerry Brown signed a sick leave law Wednesday.

While each law is slightly different, laws generally allow workers to accrue paid sick time after a probationary period of employment and include exemptions or scaled-down provisions for small businesses. The time off might be for the worker, but also the worker’s child, spouse or parent. It could be used to recover from an illness, attend a doctor’s appointment or deal with the effects of a violent incident.

While each law follows the same basic formula, its specific design can affect how broad and deep the impacts will be. In Connecticut, the legislature excluded small businesses, manufacturers and nationally chartered nonprofits, in addition to per diem workers and temporary workers. The carveouts were so extensive that the law ultimately applied to somewhere between 12 percent and 18 percent of the state’s 1.7 million workers. The Massachusetts measure, if passed, would be more far-reaching.

Nationally, about 39 percent of private workers do not have access to paid sick days, according to a March survey by the U.S. Bureau of Labor Statistics. Access to paid sick days is least common in the service industry (40 percent of service workers have it), among part-time workers (24 percent) and workers in the bottom quartile of wages (30 percent). By contrast, the benefit is widely available for workers in state and local government, where 89 percent have access to paid sick days.

Massachusetts lawmakers have introduced a paid-sick-days bill each of the last three biennial sessions, only to see the legislation stall in committee every time. Membership associations representing retailers and restaurants in Massachusetts have opposed those bills, arguing that a sick leave mandate would burden businesses with new costs.

“One size doesn’t fit all,” said Jon Hurst, president of the Retailers Association of Massachusetts. “Whether you’re a daycare center or a restaurant or a retail store, if someone calls in sick, you have to replace that person. It literally is double the payroll and that situation doesn’t exist in an office-type of setting.”

Researchers and policymakers dispute the impacts of paid sick laws, though the Center for Economic and Policy Research conducted a 2013 survey of businesses in Connecticut that highlights some of the tradeoffs with any paid-sick-leave proposal. About 11 percent of businesses said they cut employee hours after the state law passed. About 16 percent said they increased prices. At the same time, about 11 percent reported increased worker loyalty and about 15 percent reported a reduction in the spread of illnesses at work.

The Institute for Women’s Policy Research, a left-leaning think tank, estimates that the economic benefits of paid sick laws outweigh the costs. The organization assumes large savings gleaned from reducing employee turnover and smaller savings from stopping the spread of flu.