EPA told to let diesel makers disable pollution controls in winter

What it does

This bill requires the EPA to allow diesel vehicle and equipment manufacturers to disable engine derate (power reduction) and shutdown functions triggered by emissions controls when temperatures drop below 20°F, with the engine automatically resuming normal operation when it warms up. For agricultural equipment and vehicles operated in Arctic regions (north of 59°N latitude), manufacturers can permanently disable these functions. The bill states it does not waive emissions standards themselves.

Why we flagged it

The bill's operative mechanism is a regulatory exemption allowing manufacturers to disable emissions-control functions. While titled as a 'reliability' measure, its primary effect is to permit higher pollution emissions in cold weather and Arctic regions, benefiting diesel engine manufacturers at the cost of air quality.

What the text implies

• Cold-weather emissions spikes are most harmful to human health; disabling controls precisely when pollution is worst concentrates air-quality damage in winter months when respiratory illness peaks.
• Arctic and agricultural exemptions are permanent, not seasonal — they remove pollution controls year-round in those regions, not just during cold snaps.
• The bill's 'rule of construction' (Section 4) claims it does not waive emissions standards, but suspending the control functions that enforce those standards during cold weather effectively creates a seasonal/regional exemption from the standard itself.
• Manufacturers gain competitive advantage by avoiding costly cold-weather emissions-control engineering; the cost of that avoided engineering is externalized as air pollution to citizens in cold climates.

Section numbers refer to the bill text the analysis read — linked under Primary records below.

Who it affects

The bill permits manufacturers to disable pollution-control functions during cold weather, when emissions are typically highest and most harmful. While framed as a reliability measure, it allows increased air pollution exposure for citizens in cold climates and Arctic regions, offsetting any engine reliability benefit with public health cost. The permanent exemption for agricultural equipment and Arctic vehicles removes pollution controls entirely in those areas.

Who stands to gain

• diesel engine manufacturers
• heavy-duty truck manufacturers
• agricultural equipment manufacturers
• diesel vehicle OEMs

Named in the bill

Environmental Protection Agency (EPA), Clean Air Act, diesel vehicle manufacturers, agricultural equipment manufacturers, Arctic regions (59°N latitude), Section 216 of the Clean Air Act, Section 1111 of the Agricultural Act of 2014

Where it stands

3 cosponsors: 3 Republicans.

• Nov 6, 2025 — Introduced · Congress.gov: “Introduced in Senate”
• Nov 6, 2025 — Referred to Senate Committee on Environment and Public Works · Congress.gov: “Read twice and referred to the Committee on Environment and Public Works”
• Mar 11, 2026 — Hearing held · Congress.gov: “Committee on Environment and Public Works. Hearings held”
• Sep 16, 2026 — Reported out of committee · Congress.gov: “Committee on Environment and Public Works. Reported by Senator Capito with an amendment in the nature of a…”

Dates and quoted wording are Congress.gov's action record; the timeline shows status changes, not every procedural step.

Money around this bill

6 lobbying clients named this bill on 6 disclosure filings across 1 quarter, Jun 2026 to Jun 2026. Those filings disclosed $3,733,908 in lobbying spend. A filing names 20 bills on average, so that figure is what each filing reported, not a share belonging to this bill.

More lobbying clients named this bill than 82% of bills with at least one filing.

Dan Sullivan, the sponsor, reported $2,276,230 in PAC receipts in the 2026 cycle.

• Caterpillar Inc — $1,142,000 on 1 filing
• American Trucking Associations — $720,000 on 1 filing
• International Motors, LLC (formerly Navistar, Inc) — $640,000 on 1 filing
• Cummins Inc — $521,908 on 1 filing
• Volvo Group North America LLC — $430,000 on 1 filing

Lobbying Disclosure Act filings through Jul 20, 2026. A filing shows who paid to lobby on a bill it names, not what changed.