EPA greenlights gadgets for finer air particle tracking
Published Date: 4/7/2025
Notice
Summary
The EPA just approved two new gadgets to measure tiny air particles called PM2.5 and PM10-2.5, helping states keep our air clean. These new tools use smart tech to track pollution more easily and accurately. If you work in air quality monitoring, get ready to use these updated methods soon—no big costs, just better air checks!
Analyzed Economic Effects
3 provisions identified: 3 benefits, 0 costs, 0 mixed.
EPA OKs DKK-TOA PM2.5 Monitor
If you run air monitoring for a State or local agency, the EPA has designated the DKK-TOA Models FPM-377C(S) and FPM-377C (EQPM-1224-264) as an equivalent method for measuring PM2.5 in ambient air. To qualify under this designation the monitor must be configured with a standard EPA PM10 inlet and an approved PM2.5 separator (e.g., URG-2000-30EGN, BGI VSCCTM, or Tisch TE-PM2.5C), be operated with Software Firmware Version FPM4-749840 or later, have Corrected Slope Factor (FACT SLOPE) set to 1.242 and Corrected Zero Value (FACT ZERO) set to 0, and be used in accordance with its operating manual.
EPA Approves PM10-2.5 Monitor Pair Method
The EPA designated a paired-monitor method (EQPM-1224-265) using two DKK-TOA FPM-377C monitors to determine coarse particulate matter (PM10-2.5). For PM10-2.5 the pair must use one monitor approved as a PM10 monitor (EQPM-0905-156) and one approved as a PM2.5 monitor (EQPM-1224-264), be collocated 1–4 meters apart, and be operated concurrently and per their operating manuals.
Monitors Are Commercially Available; Use Rules Apply
The designated DKK-TOA monitors are commercially available from DKK-TOA Corporation (Tokyo, Japan). As designated equivalent methods, these monitors must be used in strict accordance with their operation or instruction manual and any specifications listed in the designated method descriptions; consistent or repeated noncompliance should be reported to the EPA Director, Air Methods and Characterization Division.
Personalized for You
How does this regulation affect your finances?
Personalize government policy and PRIA will tell you what this federal register document means for your household, plus every other regulation we track. PRIA reads each provision against your financial profile to show you exactly what matters to your wallet.
Key Dates
Department and Agencies
Related Federal Register Documents
2026-19072, Rescission of the Greenhouse Gas Findings for Fossil Fuel-Fired Power Plants and Repeal of Regulations for Power Plant Greenhouse Gas Emissions Under Clean Air Act Section 111
The EPA is proposing to cancel all greenhouse gas rules for fossil fuel power plants, saying the law doesn’t let them regulate these emissions for climate reasons. This change affects power plants across the U.S. and could impact future pollution limits and costs. Comments on this proposal are open until November 2, 2026, so now’s the time to speak up!
2026-19071, Partial Repeal of the Carbon Pollution Standards for Fossil Fuel-Fired Electric Generating Units
The EPA is rolling back most of the 2024 rules that limited carbon pollution from fossil fuel power plants. This change affects coal and gas plants by easing some strict limits on emissions and carbon capture technology. The new rules kick in on November 16, 2026, potentially saving money for power plants but raising questions about pollution control.
2026-18317, Updated Definition of “Waters of the United States”
The purpose of this supplemental notice of proposed rulemaking is for the U.S. Environmental Protection Agency (EPA) and the Department of the Army ("the agencies") to supplement and seek additional comment on certain aspects of an earlier proposal, published on November 20, 2025, to revise the regulations defining the scope of waters federally covered under the Clean Water Act in light of the U.S. Supreme Court's 2023 decision in Sackett v. Environmental Protection Agency. As stated in the agencies' November 20, 2025 Notice of Proposed Rulemaking (NPRM), the agencies intend for this rulemaking to provide greater regulatory certainty and increase Clean Water Act program predictability and consistency by clarifying the definition of "waters of the United States." After consideration of the public comments received on the NPRM, the agencies are issuing this notice to supplement the NPRM with additional regulatory options on certain aspects of the proposed rule.
2026-14112, Amendments and Nonconformance Penalties for Model Year 2027 and Later Heavy-Duty Highway Engines and Amendments to Inducement Provisions for SCR-Equipped Diesel Engines
Starting with model year 2027, the EPA is updating rules for big truck engines to make sure they last longer and pollute less. They’re also letting engine makers pay penalties if their engines don’t meet standards, and tightening rules for special pollution-control systems on diesel engines. These changes affect truck and engine makers and kick in soon, with public feedback due by August 29, 2026.
2026-13667, Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans
The EPA wants to give states more freedom to decide how much public input is needed when approving small air pollution sources or changes. This means local air agencies can tailor public participation to fit their community’s needs while still protecting air quality. If you’re involved in air permits, watch for comment deadlines and possible virtual hearings this summer!
2026-13263, Revisions To Establish the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6) for Public Water Systems
The EPA is rolling out the sixth Unregulated Contaminant Monitoring Rule (UCMR 6) to check for new, sneaky chemicals in public drinking water. Big water systems serving 3,300+ people and some smaller ones will test for 30 different contaminants, including certain PFAS and pesticides, to keep our water safe. Comments and feedback are open until late August 2026, and the EPA will host fun online meetings to chat about the plan!
Previous / Next Documents
Previous: 2025-05919, Combined Notice of Filings #1
The Federal Energy Regulatory Commission got a bunch of new filings from power companies about rates, solar projects, and corporate changes. These filings could affect how much you pay for electricity and when new energy projects start running. If you want to comment or keep an eye on these changes, deadlines are mostly in April and May 2025.
Next: 2025-05924, Reorganization of Foreign-Trade Zone 262 (Expansion of Service Area) Under Alternative Site Framework; Southaven, Mississippi
The Foreign-Trade Zones Board just gave the green light to expand Foreign-Trade Zone 262’s service area in Mississippi, adding Lafayette, Marshall, Panola, and Tate Counties. This means businesses in these areas near Memphis can enjoy special trade benefits that speed up imports and exports. The change kicks in soon and sticks to a 2,000-acre limit, helping local companies grow without extra costs.