• If you receive an error message related to MSXML4r.dll during the software installation, please click Ignore in the setup dialog.  This file is used by another third party HARP program and is not necessary to run HARP.  To resolve this issue, you can copy and paste the MSXML4r.dll file manually into the windows system directory (c:\windows\system32). 
• HARP Upgrade Instructions

• What is the best way to learn how to use HARP?
• HARP Tutorial (Chapter 4 of the HARP User Guide)
• HARP How-To Guides
• HARP Point Source Sample Problem
• HARP Tips to Remember
• HARP Data File Matrix
• Instructions for exporting the map and risk results from HARP to Google Earth

• AB 2588 "Hot Spots" Program
• CEIDARS 2.5 Database Structure
• Consolidated Table of OEHHA/ARB Approved Risk Assessment Health Values
• Office of Environmental Health Hazard Assessment
• USEPA Dispersion Modeling Website
• USGS Geographic Data Download

For questions about HARP, please call (916) 322-1617 or send an email to HARP support.