how far back do you want to go? ever wonder who formed the EPA in the first place?
Diesel emissions laws began with the U.S. Environmental Protection Agency (.gov) and the 1970 Clean Air Act. The laws evolved over five decades from basic smog checks to the near-total elimination of particulate matter (PM) and nitrogen oxides (NOx) through ultra-low sulfur diesel fuel and advanced exhaust aftertreatment systems.Key Milestones in Diesel Emissions Regulations
1970: The U.S. Environmental Protection Agency (.gov) is established, paving the way for the first on-road diesel engine standards.
1974: First EPA standards go into effect, targeting carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).1988: PM (soot) is officially regulated for the first time.
1991–1998: The EPA introduces progressive "Tier" standards for non-road engines and heavily restricts PM limits for on-road heavy-duty trucks.
1998 Consent Decrees: The EPA penalizes seven major diesel engine manufacturers for using "defeat devices" that secretly disabled emissions controls during highway cruising. This resulted in an agreement to meet future 2004 standards ahead of schedule.
2006: A massive mandate takes effect requiring refiners to slash diesel sulfur content from 500 ppm to 15 ppm (Ultra-Low Sulfur Diesel).
2007–2010: The EPA enforces stringent "US 2010 Standards". This requires the addition of Diesel Particulate Filters (DPF) and Selective Catalytic Reduction (SCR) technology using Diesel Exhaust Fluid (DEF).
2015: Final phase-in of the EPA's Tier 4 non-road standards is completed, achieving a 90% reduction in particulate and NOx emissions compared to older non-road engines.
at which point in this timeline was America 'great' (using Trump-speak)?
imo, 2015 was the step too far but wtf do I know about any of this stuff?
regardless... that's been the law since
wait until November...
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Crnr2Crnr ·
