Company lists · Data refreshed September 2026
Top 25 Automotive emission reduction companies based in the United States
RevenueBase identified 132 automotive emission reduction companies headquartered in the United States as of September 2026 and tracks 1,121 professional contacts across them, including 355 with verified work emails. Houston is the largest hub.
This list covers automotive emission reduction companies headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 30, 2026.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest automotive emission reduction companies based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 199 contacts → | ||||
Partial evidence “Cataler North America, a Toyota Motor Corporation affiliate, is a leading manufacturer of automotive catalysts that enhance the quality of the environment by filtering exhaust…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 2 | 70 contacts → | ||||
Indirect evidence “TRANSTEX est un chef de file des technologies propres dans le secteur des transports, qui conçoit des solutions de réduction des émissions pour améliorer l'efficacité des flottes…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 3 | 55 contacts → | ||||
Partial evidence “Dinex is a trusted global partner in advanced exhaust and emission technologies, bringing over 40 years of OEM experience directly to the North American heavy-duty aftermarket.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 4 | 51 contacts → | ||||
Strong evidence “STAX is an emerging leader in emissions reduction services.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 5 | 50 contacts → | ||||
Partial evidence “Conifer Systems designs, manufactures and installs state-of-the-art emissions control systems and provides aftermarket services to enable industries to meet and exceed their…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 6 | 48 contacts → | ||||
Partial evidence “ESW Group® was founded in 1998 as an R&D company with the goal to develop ceramic based catalytic converters for the automotive industry.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 7 | 36 contacts → | ||||
Partial evidence “Formed in 2010 and headquartered in Houston, Texas, Encino Environmental Services, LLC is an emissions testing, monitoring, and compliance support firm serving critical…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 8 | 35 contacts → | ||||
Indirect evidence “Rypos is driven to address climate change through clean air technology.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 9 | 25 contacts → | ||||
Partial evidence “Belco Technologies Corporation (BTC) is an Elessent Clean Technologies company specializing in emission control solutions for major oil refining processes.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 10 | 21 contacts → | ||||
Partial evidence “Achates Power, has developed radically improved internal combustion engines that increase fuel efficiency, reduce greenhouse gas emissions and are lower cost.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 11 | 20 contacts → | ||||
Partial evidence “ClearSign Technologies (NASDAQ: CLIR) designs and develops technologies that aim to solve the greatest challenge facing the energy industry today: capital intensive emissions…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 12 | 19 contacts → | ||||
Partial evidence “Health & Safety in the Fire & EMS Industry and Emission solutions for all other Industries.See our websites for additional & Ward Diesel & Ward Clean Air Products History: Ward…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 13 | 16 contacts → | ||||
Indirect evidence “We offer technical solutions to help solve today’s challenges in the global market place in the fight against pollution from internal combustion engines (ICE).” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 14 | 16 contacts → | ||||
Partial evidence “Global Pioneer and Leader in DPF & DOC Cleaning, Restoration, & Emissions Systems” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 15 | 12 contacts → | ||||
Indirect evidence “As the trusted advisor and collective voice of organizations in Ohio that make and use advanced, cleaner fuels, vehicle technologies and mobility solutions, we are committed to…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 16 | 11 contacts → | ||||
Partial evidence “AERINOX is an environmental engineering company supplying reliable and cost-competitive emissions solutions to the North American stationary engine markets.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 17 | 9 contacts → | ||||
Partial evidence “Today FleetServ provides a full range of diesel emissions solutions, eliminating all of the stress and headache often associated with diesel emissions.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 18 | 9 contacts → | ||||
Partial evidence “Bionomic Industries has the application expertise, equipment and complete systems to reliably solve your air emission problem in the most cost effective manner.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 19 | 8 contacts → | ||||
Indirect evidence “Landi Technologies is a leading manufacturer of innovative technologies for eco-friendly commercial vehicles.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 20 | 8 contacts → | ||||
Indirect evidence “MillerCat designs, engineers, and manufactures 100% CARB-certified catalytic converters, exhaust accessories, and catalytic converter anti-theft security protection Cat Shields.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 21 | 8 contacts → | ||||
Partial evidence “CUTS EMISSIONS RCT has developed the RCTClean 3.0gr Solution to enable 2-stroke lean-burn (2SLB) natural gas pipeline engines to meet the new EPA Good Neighbor Rule 3.0gr NOx…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 22 | 7 contacts → | ||||
Partial evidence “Sandbox Carbon produces equipment to capture carbon emissions at the point of emission.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 23 | 6 contacts → | ||||
Indirect evidence “In a world where environmental responsibility and corporate accountability are more crucial than ever, Redecam stands at the forefront of innovation and sustainability.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 24 | 6 contacts → | ||||
Partial evidence “MineTerra is an industry leading emissions control solutions provider.” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
| 25 | 6 contacts → | ||||
Strong evidence “Emissions reduction equipment and services for the Natural Gas Industry Natural Gas Powered Mobile Compression | Recompression/Cross-compression/Pipeline Evacuation Temporary…” Source: RevenueBase Database · checked Sep 30, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: automotive emission reduction companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names automotive emission reduction companies.
- Partial evidence
- Its own public description names part of automotive emission reduction companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name automotive emission reduction companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 132 automotive emission reduction companies based in the United States
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Automotive emission reduction companies based in the United States at a glance
As of Sep 30, 2026Companies by employee count
Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 132 companies.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among automotive emission reduction companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- What qualifies
- Companies headquartered in the United States whose own description of what they do matches “automotive emission reduction companies”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names automotive emission reduction companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among automotive emission reduction companies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 355 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 30, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names automotive emission reduction companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many automotive emission reduction companies are there based in the United States?
RevenueBase identified 132 automotive emission reduction companies headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
Cataler North America, headquartered in Lincolnton, tops this list with the largest team on record.
Which city has the most automotive emission reduction companies?
Houston leads with 5 headquartered companies, followed by New York (3) and Rochester (3).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 355 verified decision-maker contacts tracked across these 132 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 30, 2026.
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About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.
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