Great link, thank you! <A HREF="http://www.epa.gov/otaq/consumer/dev-fs.pdf" target="_blank">http://www.epa.gov/otaq/consumer/dev-fs.pdf</A> was interesting. This is who tested DynoValve: California Environmental Engineering 3231 S. Standard Santa Ana, CA 92705 (714)545-9822 Joseph Jones I'll let you all know if I find anything out from them. _moose