>>185029, >>185030, >>185031, >>185032, >>185033, >>185034, >>185035, >>185036, >>185037, >>185038, >>185039, >>185040, >>185042, >>185043, >>185044, >>185045, >>185046, >>185047, >>185048, >>185049, >>185050, >>185051, >>185052, >>185053, >>185054, >>185055, >>185056, >>185057, >>185058, >>185059, >>185060, >>185061, >>185062, >>185063, >>185064, >>185065, >>185066, >>185067, >>185068, >>185069, >>185070, >>185071, >>185072, >>185073, >>185074, >>185075, >>185076, >>185077, >>185078, >>185079, >>185080, >>185081, >>185082, >>185083, >>185084, >>185085, >>185086, >>185087, >>185088, >>185089, >>185090, >>185091, >>185092, >>185093, >>185094, >>185095, >>185096, >>185097, >>185098, >>185099, >>185100, >>185101, >>185102, >>185103, >>185104, >>185105, >>185106
* EPA clarified in its August 2025 guidance that, for agricultural equipment, the allowable inducement period may be up to 100 hours, giving operators significantly more time to diagnose and resolve
issues. Previously, the inducement period for agricultural equipment was only 4 hours before the
equipment went idle. More information on the August guidance can be found here.
* Farmers, truckers, and other equipment operators have made clear that these unnecessary inducements lead to operational delays, reduce productivity, compromise safety and impose real economic hardship.
## Ensuring Reliable DEF Systems
* EPA's March 2026 guidance clarifies that alternative monitoring approaches are allowed under existing regulations and confirms that approved NOx sensor-based software updates can be installed on existing engines without being treated as illegal tampering under the Clean Air Act.
* This is in line with EPA's February 2026 Right to Repair clarification guidance.
* EPA encourages manufacturers to adopt these more reliable monitoring technologies, including NOx sensors, to improve the reliability of their SCR systems in both existing and future products.
* The increased use of these alternative approaches will greatly reduce the frequency of false failures and unnecessary inducements that have been associated with traditional sensor technologies.
## Prosperity for American Operators
* This action increases flexibility for manufacturers and allows them to move away from failure-prone technologies toward more reliable solutions that better serve operators in the field.
* By improving system reliability, this guidance gives consumers greater confidence that their emissions control systems will function as intended without unnecessary disruptions.
* The Small Business Administration estimates that these improvements will deliver significant economic benefits, including annual savings of approximately $6.7 billion for light-duty truck operators, $2.7 billion for heavy-duty truck operators, and $4.39 for agricultural vehicle operators.
## Addressing Americans' Concerns
* EPA is taking this action in response to the persistent and well-documented concerns of farmers, truckers, and other operators who rely on diesel-powered equipment to keep the American economy moving.
* This guidance does not weaken or remove emissions standards. Instead, it ensures that those standards are met in a way that works in real-world conditions and do not impose unnecessary burdens on the countless people working across the country who rely on this equipment every day.