Hair Analysis Drug Screen

Topic 34089 | Page 1

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newbie's Comment
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So I took up delta-8 “hemp flower” for a couple months in 2023, and put it down at the end of October. I took it up to assist with sleeping, but it wound up not really helping all that much.

Some time goes by.

I had been tossing around the idea of getting my CDL for a couple months at this point, so I started looking into it and learned about the hair tests that all the megas do (this was around late February of this year, so I have not ingested any type of substance for about 4 months at this point). I was in no position to move forward with getting my CDL at that time, but I figured I’d help my future self out and shaved my body clean.

So it’s now been 7 months with no substances, all my hair has grown back (except my head, I have shaved my head since I was in my early-20s). I’m in a CDL program, passed their UA test no problem, and should have a job at the beginning of July. At that point it’ll be 8-ish total months with no substances, and 4 month old hair.

I should be okay passing that hair analysis drug screen, wouldn’t you think?


Commercial Driver's License (CDL)

A CDL is required to drive any of the following vehicles:

  • Any combination of vehicles with a gross combined weight rating (GCWR) of 26,001 or more pounds, providing the gross vehicle weight rating (GVWR) of the vehicle being towed is in excess of 10,000 pounds.
  • Any single vehicle with a GVWR of 26,001 or more pounds, or any such vehicle towing another not in excess of 10,000 pounds.
  • Any vehicle, regardless of size, designed to transport 16 or more persons, including the driver.
  • Any vehicle required by federal regulations to be placarded while transporting hazardous materials.
Doug S.'s Comment
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you should be fine as long as it’s been that long I wouldn’t worry about it but I would suggest staying off it permanently if your going to take up a driving career now

Highway 44's Comment
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I can't and won't tell you that you will or will not pass a hair follicle drug screen at this stage of your timeline. Here is some information for review. Please take it all with a grain of salt, as I implore you to due diligence; do your homework in order to make the best, most informed decision on “when” to hair test on your current timeline.

A hair follicle drug screen only requires a specimen size of 1.5-inches; however, a more sizable sample can be taken if the donor’s hair is longer at the time of collection. Human hair growth rates differ individually, but the average is at a growth rate of 0.5-inches per month; therefore, a 1.5” sample yields a minimum 3-month substance usage history (or lack thereof), more history if the hair sample is longer than 1.5-inches at the time of collection. A substance’s metabolic rate varies by both substance type and by an individual's body type. My assumption, in your case, the substance (in question) is THC or a variant thereof. Simply put, the THC in your body can remain in fat cell storage (for an indefinite period of time) until fully metabolized from the body. Again, the rate of metabolism varies by substance type, along with other factors such as an individual's unique body type (metabolic rate), plus the rate and frequency of usage e.g., heavy, chronic usage over the length of an individual timeline.

The shaving of the body hair is usually the step to take once in abstinence of substance usage and in confidence the body has both fully metabolized a substance and is clean of such substance. This ensures hair growth from that point forward to be a clean slate. I believe the general consensus, in terms of metabolic rate, is a wait period of 6-months to 1-year to ensure a clean slate of body hair growth. The DOT only regulates the urinalysis drug screen, not the hair follicle; the hair follicle drug screen is strictly at the company’s discretion. If you want to be certain come July, pre-hire , you could independently hair test at your cost.

Good luck and good journey.


Department Of Transportation

A department of the federal executive branch responsible for the national highways and for railroad and airline safety. It also manages Amtrak, the national railroad system, and the Coast Guard.

State and Federal DOT Officers are responsible for commercial vehicle enforcement. "The truck police" you could call them.


What Exactly Is A Pre-Hire Letter?

Pre-hire letters are acceptance letters from trucking companies to students, or even potential students, to verify placement. The trucking companies are saying in writing that the student, or potential student, appears to meet the company's minimum hiring requirements and is welcome to attend their orientation at the company’s expense once he or she graduates from truck driving school and has their CDL in hand.

We have an excellent article that will help you Understand The Pre-Hire Process.

A Pre-Hire Letter Is Not A Guarantee Of Employment

The people that receive a pre-hire letter are people who meet the company's minimum hiring requirements, but it is not an employment contract. It is an invitation to orientation, and the orientation itself is a prerequisite to employment.

During the orientation you will get a physical, drug screen, and background check done. These and other qualifications must be met before someone in orientation is officially hired.

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