People working at jobs with unsteady hours and low pay deserve better than they’ve received in recent years, as larger economic forces have conspired to cut their hours, freeze their wages and weaken their benefits. Those concerned with helping them, however, should push for improvement on a number of policy fronts, not for changes in the Affordable Care Act that would diminish that law and harm the many more Americans who work full-time.

Evidence suggests a bill sponsored by Sen. Susan Collins, R-Maine, would do just that. Known alternately as the “Forty Hours is Full Time Act” and the “Save American Workers Act,” the bill would change the the ACA’s definition of full-time employment from 30 hours per week to 40.

Under the health reform law, employers with more than 50 full-time employees are required to offer health insurance to them, or pay a penalty. Supporters of the bill argue that this provision gives employers reason to cut the hours of employees who work anywhere near 30 hours a week in order to avoid the insurance mandate.

That has not happened so far. A report early last year by the nonpartisan Congressional Budget Office did not find any increase in part-time work less than 30 hours a week as a result of the ACA. That has been backed up by subsequent analysis from the Federal Reserve Bank of San Francisco and the Urban Institute.

Of course, that may change as the mandate goes into effect and more employers respond. But even if those fears materialize, far more workers would be affected by Collins’ bill.

According to the Bureau of Labor Statistics, only 7 percent of the workforce works between 30 and 34 hours a week, while around 44 percent work exactly 40 hours a week.

So by raising the threshold for the employer mandate, Congress would make a far greater portion of the workforce vulnerable to losing hours, as employers would have to cut only those 40-hour-a-week workers by an hour or so to avoid the cost of insurance.

The change also would allow businesses to forgo offering health insurance to employees who work between 30 and 39 hours.

Most of those employees then would seek insurance through the ACA exchange or Medicaid, shifting the cost from employers to the government and adding to the budget deficit $53 billion over 10 years. The remaining employees would be left without insurance.

That’s in direct opposition to the aims of the Affordable Care Act, which a cynic would say is the point of the bill. The proposal, after all, is backed largely by Republicans, who have made repeal of the ACA, either piecemeal or all at once, a center piece of their platform.

If the bill is out of concern for part-time workers, lawmakers would be better off supporting initiatives in education, skills training, public transportation and a more modern minimum wage than changing the ACA’s employee mandate.

Yes, a relative few likely will see their hours reduced unless the mandate is changed. But many more will benefit if it isn’t.