I recently got offered an internship at BlackRock as an analyst and I am afraid they will do a hair test. They already said they will be doing an FBI background check instead of the traditional one, so this makes me think they will dish out the cash for a hair test. I've smoked probably 4 or 5 times in the past few months, so I'm screwed if that's the case.
Hair drug tests at blackrock
The simple answer is no. The firm will probably not require a hair sample for an intern. If they did require a hair test there's no way around it. Even if you shave your head they can pull an eyebrow or leg hair. Unfortunately, there's no guarantee that any random shampoo will help you either.
It's much more likely that you'll be asked to provide a urine sample.
from certified user @ElliotWaveSurfer
and I personally know about a dozen people who work or have worked at BlackRock (they recruit like crazy at my school.) They have never taken a hair test. A few were even dilute the first time and the firm just let them take the retest whenever as long as it was before employment started.