So I plan on applying for an electrician job at Amtrak soon. I am aware of the drug testing methods used. I used to smoke weed up until 2 months ago and I don’t plan on using any drugs again in the future. With that being said, I know hair tests will show anything used within the last 3 months. But some people say it can test back as far as 6 months. Would I be safe to apply for the job in the 4-5 month period of being clean or should I wait longer than that? Again, I am drug free and I look forward to working for Amtrak, however I do not want to blow it on something silly like failing a drug test. Any advice is appreciated!