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Industry leaders raise concern about proposed EPA NOx rule

From Transport Topics.

The Environmental Protection Agency is proposing its first new rules governing heavy-truck nitrogen oxide emissions in two decades, but engine manufacturers say the proposals would be difficult to meet and counterproductive because they could slow the move to cleaner technology.

EPA is proposing two options for reducing nitrogen oxides (NOx), which include nitric oxide, nitrogen dioxide and other air pollutants.

Option 1 would place a limit of .035 gram of NOx per brake horsepower-hour for model years 2027-30, followed by .02 gram in the years following. The agency notes NOx standards would be 90% lower than they are today, when the standard is .2 gram. The option mimics a California rule. Option 2 would require .05 gram starting with model year 2027.

The proposals would also increase warranty periods, which currently are 100,000 miles or five years under federal law. Under Option 1, the warranty period would increase to 450,000 miles or seven years by 2027 and to 600,000 miles or 10 years by 2031. Under Option 2, warranties would increase to 350,000 miles or five years by 2027.

Likewise, EPA wants to increase the currently required useful life of 435,000 miles for heavy-duty vehicles — useful life being how long the manufacturer must certify expected tailpipe emissions compliance. EPA is considering increasing the useful life under Option 1 to 600,000 miles or 11 years in 2027 and then to 800,000 miles or 12 years in 2031. Under Option 2, it would increase to 650,000 miles or 10 years in 2027.

The agency plans to finalize the change before the end of 2022. The proposal stems from an executive order by President Joe Biden. EPA also plans to raise greenhouse gas emission standards starting with model year 2027.

See the complete article online at Transport Topics.