Here is a link to the Wa. State Ecology dept. It explains the emissions testing requirements. If your rig is old enough, it needn't be tested! (//images/smiles/icon_biggrin.gif)
http://www.ecy.wa.gov/programs/air/cars/emischeckfaqs.htm (http://www.ecy.wa.gov/programs/air/cars/emischeckfaqs.htm)