HealthyCar.org — Methodology

A portable X-Ray Fluorescence (XRF) device was used to analyze the elemental composition of vehicle and child car seat components in this guide. A total of 15 components from each vehicle were selected for sampling, including: the steering wheel, shift knob, armrest/center console, dashboard, headliner, carpet, seat front, seat back, seat base, hard doortrim, soft doortrim, body sealer, wiring, window seal, and wheel weights. Vehicle ratings were calculated based on the XRF results from the 12 vehicle components that were tested on all vehicles. Wheel weights, sealers and wiring were not sampled in every vehicle and thus were not included in the overall ratings.

Child car seats were evaluated using a similar method. The major components in each car seat were sampled, including the seat cushion, foam backing, seat base, seat belt clip and sun shade (when available). Different components were analyzed for different types of car seats. For example, infant seats include sun shades, whereas convertible and booster seats do not. Car seat ratings were calculated based on the XRF results from the components that were sampled on all seats of the same type.

The components were selected based on the following criteria:

Potential of exposure, i.e. components that drivers or passengers come in contact with, that are subject to abrasion, or that otherwise release vapors or particles to the environment;

Surface area and relative size of component;

Potential to off-gas or degrade during heat and/or UV-ray exposure;

Ease of access to component for sampling.

For both vehicles and child car seats, the elements tested for include: Antimony, Arsenic, Bromine, Chlorine, Chromium, Cobalt, Copper, Lead, Mercury, Nickel and Tin. These components were chosen for two primary reasons: 1) They could be easily and quickly identified using non-destructive methods. Sampling for this project was limited to new vehicles, which prevented the use of any testing that would damage vehicle components. 2) These elements have already been subject to regulatory restrictions and/or voluntary limits by industry associations or third party environmental certification organizations. These "Chemicals of Concern" may be of impact to the environment and health during all phases of a product's lifecycle, including production, use and end-of-life.

For a detailed description of the HealthyCar.org vehicle and child car seat rating systems and methodology, download the fully referenced report.