Clean Truck Check Credentialed Tester

Clean Truck Check in Escondido, CA

14 credentialed testers in Escondido.

Testers in Escondido

Trucking activity in San Diego County

Clean Truck Check applies to heavy-duty vehicles that operate in California — including out-of-state trucks based here that run loads west.

Trucking establishments
936
Trucking employees
7,861

Source: FMCSA MCMIS carrier census, US Census County Business Patterns 2021.

Air quality context in and around Escondido

Annual aggregate readings from EPA Air Quality System monitors within about 25 miles of Escondido, reporting year 2025. Clean Truck Check exists to reduce real-world emissions from heavy-duty vehicles — the numbers below are the local baseline those rules are designed to improve.

PM2.5
8.02 Micrograms/cubic meter (LC)
8 monitors · 111,105 observations · 183 days above standard
Nitrogen dioxide (NO₂)
10.65 Parts per billion
6 monitors · 94,396 observations · 0 days above standard
Ozone (O₃)
0.04 Parts per million
7 monitors · 213,728 observations · 25 days above standard

Source: EPA Air Quality System (AQS) API. Reporting year 2025. Last fetched 2026-05-18.