Hey. If he us only using heroin then he can provide a clean urine as little as a few days after use. Methadone and other longer opiates stay in the system way longer. But heroin , days.
Was it a urine test or from the mouth ???
Both test are usually pretty good as it’s what company’s use to test there employee’s.. But can be fiddled using a clean persons wee if the person new about the test before hand and got hold of clean for the day..
If he is using. He will be telling you what ever .. But if he is doing it in your house , you will soon catch him at.