Comments on the Joint Proposed Rulemaking to Establish Light- Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards Docket No. NHTSA–2009–0059 and

Report

10/2009

Pinpointing the causes of a vehicle crash, and any fatalities or serious injuries that occur in

crashes, is a very difficult task. Many variables can contribute to one vehicle model having a

higher risk on-road risk than another model; these variables can be grouped into three general

categories, driver characteristics and behavior, vehicle attributes and condition, and crash

location and environment.

The 2003 NHTSA study (Kahane, 2003) did a thorough job accounting for many of the variables

that may affect injury and fatality outcomes in crashes. However, even this comprehensive

analysis did not account for all of these variables; indeed, it may not be possible to fully account

for all of the important variables that determine crash outcomes. I have critiqued this analysis in

comments submitted for previous NHTSA rulemakings (Wenzel and Ross, 2004a; Wenzel and

Ross, 2004b; Wenzel and Ross, 2005; Wenzel and Ross, 2008).

2009