Carbon Monoxide Categorical Hot-Spot Finding
Provisions for a carbon monoxide (CO) categorical hot-spot finding were included in the January 24, 2008 final conformity rule amendments at 40 CFR 93.123(a)(3) and explained in the preamble at 73 FR 4432-4434. 40 CFR 93.123(a)(3) states, "DOT, in consultation with EPA, may also choose to make a categorical hot-spot finding that §93.116(a) is met without further hot-spot analysis for any project described in paragraphs (a)(1) and (a)(2) of this section based on appropriate modeling. DOT, in consultation with EPA, may also consider the current air quality circumstances of a given CO nonattainment or maintenance area in categorical hot-spot findings for applicable FHWA or FTA projects".
PDF files can be viewed with the Acrobat® Reader®
FHWA's CO Categorical Hot-Spot Memo and Finding
Technical Documentation and Resources
- FHWA's CO Categorical Hot-Spot Finding Tool
- FHWA's CO Categorical Hot-Spot Finding Technical Document
- MOVES Files
The MOVES2010b files used for the CO categorical hot-spot analysis.
- CAL3QHC Files
The CAL3QHC model, Version 2.0 files used for the CO categorical hot-spot analysis.
- Recording of CO Categorical Hot-Spot Finding Webinar (slides HTML or PDF, 1.4MB) (February 26, 2014) - FHWA presentation the CO categorical hot-spot finding and how to use it on upcoming projects.
- Using MOVES in Project-Level Carbon Monoxide Analyses (PDF, 1.94MB)
- Guideline for Modeling Carbon Monoxide from Roadway Intersection (PDF, 532KB)
- Complete Transportation Conformity Rule (HTML or PDF, 287KB)
- Federal Register including Appendix W, Volume 70, Number 216, Wednesday, November 9, 2005, Pages 68218-68261