Oregon also has a law requiring you to submit to a breath test if asked by an officer. If you refuse, the DMV will suspend your license for between 1 and 3 years, depending on your prior history involving breath tests. Failing a breath test, or blowing over the legal limit, also will lead to a license suspension, but it will not be as long as it would have been had you refused a breath test.
Either way, a prosecutor may choose to proceed with DUI charges anyway.