Instructions for using the Human Exposure Model Version 1.3.1 (AERMOD version) for Single Facility Modeling, and instructions for using the Human Exposure Model Version 1.3.1 for Multiple Facility Modeling with Risk and Technology Review Summary Programs.

• Single-facility HEM-3 User's Guide - April 2014 (PDF)(93 pp, 2 MB)
• Multi-facility HEM-3 and RTR Summary Programs User's Guide - April 2014 (PDF)(53 pp, 1 MB)