A key proposal that will be considered is issuing “pollution tickets” to trucks over 14,000 pounds that exceed regulations when their exhaust is tested. The trucks represent about three percent of vehicles on California’s roads, but due to their size and amount of time on the road, make up over 50 percent of the pollution created by automobiles annually.

The proposal would allow for the construction of more unmanned monitoring stations, of which the state already has two, where a truck drives through a toll booth-like structure, and a device captures and tests exhaust from the truck and license plate cameras identify trucks that exceed emissions limits.

Advocates for the proposal say it would be the most important action taken to reduce pollution in California in at least 12 years, where the smog in the air causes it to be ranked among the unhealthiest in the country every year.

State officials said the estimated improvements to the air quality could prevent over 7,000 respiratory illness-related deaths over the next three decades, and save over $75 billion in medical costs.

In addition, California’s Air Resources Board is also set to evaluate Thursday a separate proposal from the state Legislature to ban the sale of new leaf blowers, lawn mowers, portable generators and other products that use gas-powered generators.

Previous studies cited by the state’s regulators have shown one hour of running a gas powered leaf blower is roughly equivalent to driving a gas engine car about 1,100 miles.

The rules would require these big trucks—including ones from other states passing through California—to be tested at least twice per year to make sure they meet the state’s standards for particulate matter and ozone pollution. Passenger cars are already required to get smog checks.

Newer trucks have sensors on board that can monitor emissions and send data to the state.

“(The rules) have some significance for climate, but what we’re really talking about here is the smog and the particulate matter that is making people sick and killing people,” said Bill Magavern, policy director for the Coalition for Clean Air, a statewide advocacy group.

The proposal is one of a flurry of forthcoming changes that could dramatically reshape consumer and industry behavior in the nation’s most populous state that, were it an independent country, would have the world’s fifth-largest economy.

Next year, regulators are poised to tighten emission standards for barges, ferries, fishing boats and tugboats that line California’s coastal cities.

And, further down the road, regulators plan to ban the sale of all new gas-powered cars by 2035.

“These are the decisions we have to make if we’re serious about reducing our reliance on fossil fuels and leaving future generations with healthier communities,” said Assemblyman Marc Berman, a Democrat from Palo Alto who authored the law requiring the ban on new gas-powered lawn equipment.

While the new smog check rules for big trucks will have the largest impact on air quality—preventing more than 680,000 tons of smog by 2050—banning the sale of new gas-powered lawn equipment will be the rule consumers notice the most.

Car engines have advanced over the years to pollute less. But the small engines that power most lawn equipment haven’t made as much progress.

“Nobody will have to give up or stop using equipment they already own. The force of this regulation falls on manufacturers,” Berman said.

The rules would have the biggest impact on professional landscapers, who rely on gas-powered equipment to do multiple jobs per day. California lawmakers included $30 million in the most recent state budget to assist these companies converting to battery-powered equipment. But on Thursday, some landscapers testified that equipment would not be as reliable.

Trucking companies and small engine manufacturers have mostly complained about how fast these new standards would be imposed. Both the smog check rules for trucks and the ban on the sale of new gas-powered lawn equipment would be fully implemented by 2024, while a similar ban on sales of new gas-powered generators would take effect in 2028.

Chris Shimoda, senior vice president for government affairs with the California Trucking Association, said the industry is suffering from a shortage of drivers and parts because of global supply chain disruptions. He said one sensor that measures diesel exhaust fluid that normally costs around $300 now can cost $7,000 or more.

“We just want to make sure that, again, anybody experiencing those sorts of issues is not left high and dry,” Shimoda said.

Jeff Coad, vice president for marketing and product management for the small engine manufacturer Briggs & Stratton, said the company is ambivalent about how their products are powered but said it won’t have enough time to fully comply.

“Converting a product such as a large zero turn mower from gas to lithium battery power is not just a matter of replacing the engine with the battery,” he said, adding the development time can take up to two years.

Liane Randolph, chair of the California Air Resources Board, said the state is sensitive to those concerns, adding that regulators do a careful analysis of both the costs and the health benefits of any proposed rule.

“These regulations result in less trips to the emergency room, less long term health impacts, and, frankly, less medical costs for the community,” she said.

The Associated Press contributed to this report.