The Environmental Protection Agency (EPA) recently announced changes to the Nitrogen Oxide (NOx) ruling.
First, they did not change the existing standards to reduce NOx emissions to 0.035grams/horsepower hour. The changes instead address the practical, or impractical, aspects of the prior ruling.
They removed the requirement to derate (significantly reduce power or halt engine function entirely) when the diesel exhaust fluid (DEF) sensor flags an issue. Instead, there will be visual and/or audible alerts to the issue.
They rescinded the upcoming warranty requirements of 10 years/450,000 miles in favor of the existing warranty provisions of 5 years/100,000 miles.
They delayed the effective date of the useful-life provision to begin in 2030 rather than 2027.
They created a nonconformance penalty (NCP) mechanism, which will allow equipment manufacturers to pay a per engine, per degree of non-compliance penalty if they are unable to achieve the 2027 NOx standard on time