You shouldn't have to pass one to get a job.
Urine tests are frequently used to terminate employees even though they don't determine whether or not someone is under the influence of drugs. They don't even test for drugs, they only test for drug metabolites so they only show if a person has used drugs recently (4 hours to 2 months). They're also incredibly easy to cheat.
The only method I've ever personally practiced to pass one is abstinence, yet I've still had 2 false positives and it's not much fun proving a false positive wrong. I'm still blacklisted for life from donating plasma in the U.S. probably due to something I ate that contained poppy seeds.
Ask yourself this question. Would you trust a breathalyzer to determine whether or not you are currently drunk if it were only capable of determining whether or not you've consumed alcohol during the last several weeks?