Correlation of Data on Mercury Switches/Vehicle for New York Program

March 2005

The following information was provided by Tom Corbett of the New York State Department of Enviromental Conservation (NYSDEC),
project manger of the automotive mercury switch collection program. The NYSDEC automotive mercury switch program has collected over 46,000 switches, or 102 lbs of mercury, from 1998 to date. The program does precise measurement of the number of switches collected from each of the nearly 60 participating suppliers (i.e. automotive recycling yards). The switch collection data for some individual suppliers has been correlated to the number of cars sent to shredder facilities by these suppliers. The data on the number of cars processed and sent to shredders was obtained directly from the individual suppliers. The data on the number of switches obtained from the suppliers is from a spreadsheet maintained by NYSDEC.

The Michigan Mercury Switch Study (PDF file) concluded that there are approximately 0.5 Hg switches /vehicle based on a sample size of neary 1400 vehicles. The New York data is in agreement on the 0.5 Hg switch/vehicle factor, and confirms this factor with a sample size that is nearly ten times larger.

Spreadsheets linked to below show calculations of the number of mercury switches per vehicle at two facilities in Western New York. The names of the facilites providing this data are being withheld. At facility x, where the business model is to rapidly process vehicles and ship them to a shredder for their steel scrap value, there were 0.5 mercury switches per vehicle processed. Autos processed at facility x include a representative mix of ages. At facility z, where the business model is to buy newer model vehicles for their parts resale value, and then scrap the vehciles after holding them for 3-4 years, there was an average of 0.4 mercury switches per vehicle processed. Autos processed at facility z are newer than the typical end-of-life vehicle, and therefore include a higher percentage of recent models that do not contain mercury switches. In addition, facility z sells many hood and trunk lids with switch assemblies as replacement parts, reducing the number of switches collected.

See information on auto mercury switch removal