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CDL Drug & Alcohol Test Methods & Detection Times

Last Updated: May 13, 2016
On December 4, 2015, the FAST Act transportation bill was signed into law by President Obama. Among other provisions, it allows for hair follicle drug testing as a DOT-approved method, but not until the Department of Health and Human Services establishes guidelines for testing, which must be completed within a year.

What New Drivers Need To Know About Methods of Drug Testing:

CDL drivers and potential drivers will be required to submit to drug and /or alcohol screening at any time in the pre-employment or employment process. DOT regulations prohibit drivers from refusing a drug or alcohol test.

Currently, the only legally accepted method to satisfy Federal DOT drug testing requirements is through urinalysis (UA), though many companies are using hair follicle testing in addition to UA. This means that while trucking companies are required by the FMCSA to use UA to test for drugs, they are allowed to also use hair follicle testing as a more thorough screening method for their own internal purposes.

Drivers will be tested for the presence of Schedule 1 narcotics and also prescription drugs. In some cases drivers will also undergo alcohol testing.

When a drug is processed through the body, it produces metabolites Substances created as by-products of drugs during the metabolic processes (chemical reactions) in the body.which collect in the bloodstream and hair follicles. Drug tests are used to detect the presence of these metabolites.

Aside from the obvious safety issues surrounding CDL drivers who use drugs, drug abuse in the workplace puts employers at a greater risk for higher insurance rates, as well as liability issues when it results in accidents or injuries.

Generally, a refusal to take a drug or alcohol test will be considered the same as a failure. In some cases, inability to produce enough urine or hair to be properly tested will be considered a refusal. A failed DOT drug or alcohol test will become part of a drivers permanent record. Drivers will be given ample opportunity to produce a sample, as detailed here: DOT Problems In Drug Tests

DOT Drug and Alcohol Testing Employee Handbook

Factors That Affect Drug and Alcohol Detection Times:

While there are generally accepted detection times, there are many factors that can impact urinalysis drug detection time frames, including:

  • Amount of drug used: The higher the amount, the longer the detectable time period.
  • Tolerance: Regular users may require higher dosages to achieve the desired effect.
  • Length of regular use: The longer a drug is used, the longer the detectable time period.
  • Hydration: Detection times will generally be lower for a well-hydrated body.
  • Body size: Presence of substances may be detectable longer in larger bodies.
  • Metabolism Rate: The faster the metabolism, the faster a substance will pass through the system,
  • Body Fat: Substances may stay in the body longer in people with higher body fat percentages.
  • Method Used: Drugs that are ingested in pill form may take longer to leave the system.
  • Age: Generally, substances will not be flushed as quickly from the body the older it gets.
  • Diet: Certain foods affect the metabolism of drugs through the liver.

Urinalysis (UA):

Urinalysis, in addition to testing for drug use, can be used as an indicator of overall health, to detect kidney and metabolic disorders, urinary tract infections, and blood sugar issues (diabetes).

Urinalysis is the most common method of drug-screening used, and is currently the only method accepted to satisfy Federally-mandated testing. Generally, urinalysis will test for drug use within a 2-10 day window, but the type of drug and frequency of use will cause the detection window to vary wildly.

Steroid use can generally be detected anywhere from 14 days to 3 months, depending on the type and frequency of use.

Heavy marijuana use could be detected through urinalysis for up to 60 days. Passive exposure (second-hand smoke) will generally not give a positive test if exposure is limited.

Samples collected in the morning are more desirable for testing, as they will be more concentrated and likely show more abnormalities.

Urinalysis Testing & Examination Phases:

A complete urinalysis will be made up of 3 separate testing phases:

  • Visual Examination:

    The color, concentration, and clarity will be evaluated.

  • Chemical Examination:

    Normally, specially treated test strips will be dipped in the urine, and specially treated sections will change colors to give the technician results, either to determine the presence or absence of drugs, or to assess other general health issues.

  • Microscopic Examination:

    Will not normally be performed as part of a drug test, except in the case of abnormal findings during the visual or chemical examination.

Urinalysis Detection Times: It cannot be stressed enough that these time frames are approximate, and based on many variables. Potential drivers would be advised to refrain from using any substance which could give a positive result for at least 90 days prior to starting the CDL process. These times should only be used as general guidelines, as many factors can determine how long metabolites will be detectable in a body.

  • Marijuana Detection Times: No one can really tell how long a person may test positive for marijuana, as it depends both on the amount and frequency of use, and the metabolism rate of that particular individuals body.

    • Usage 1 time only: 1-8 days.
    • Usage 2-4 times per month: 11-18 days.
    • Usage 2-4 times per week: 23-35 days.
    • Usage Daily: 33-48 days.
    • Extreme daily usage: 49-63 days.
  • Cocaine:

    Generally accepted time frames for benzoylecgonine (the metabolite of cocaine that is tested for) to show in UA are:

    • Casual or single dose users: 1-5 days.
    • Regular or high dose users: up to 8 days.
    • Heavy or chronic users: as long as 14-28 days, or longer.

    Use of alcohol or caffeine alongside or after using cocaine will lengthen the amount of time it takes for Benzoylecgonine to be eliminated.

  • Opiates:

    Common opiates include morphine, codeine, Methadone, Hydrocodone, and Oxycodone. Opiates and morphine derivatives will generally be detectable in urine for 1-12 days, depending on frequency of use and amount of dosage.

  • Amphetamines and Methamphetamines:

    In general, amphetamines and methamphetamines have a detection period of 1-5 days in urine,

  • Phencyclidine – PCP, Angel Dust:

    PCP is stored in fatty lipid tissue, and can be released into the bloodstream for up to several weeks. General guidelines are 1-10 days for casual use, and 1-4 weeks for heavy or chronic users.

Hair Follicle Testing Methods and Facts:

All substances will remain in the hair follicle until hair is cut off. Drug use can be detected through hair follicle testing after approximately 5-10 days, the average time that it will take for affected hair to grow past the scalp. Most hair follicle drug tests will test for a period of 90 to 120 days. As the average human hair grows about 1/2 inch per month, that would require about 1 1/2 inches of hair for testing.

Hair on a person's head grows an average of 1/2-inch per month, and the average length of hair is 1 1/2-inches. TruckingTruth did not actually make those measurements, it's all science-y statistical stuff.

Therefore, the normal standard is for the trucking companies to use hair follicle testing to check back 90 days for the presence of metabolites indicating drug use. Hair is cut as close to the scalp as possible. The minimum amount of time tested is normally about 1 month (1/2 inch). The longer the hair, the farther back the test can trace drug activity.

If the hair on the head is not long enough, body hair can be substituted. Body hair grows slower, and is normally replaced yearly, so it is more difficult to accurately represent a time frame.

Hair follicle testing has been shown to be more effective than urine analysis in detecting low-level drug use, as most drugs are rapidly excreted and undetectable with urinalysis within about 72 hours. Marijuana screening is known to be slightly less effective when using the hair test, but is accepted as a rough equivalent.

Around 70-100 hairs are needed to perform testing on hair follicles, or roughly the diameter of a pencil. Excess hair that is not used for testing will normally be kept in the chain-of-custody container, for various periods of time, depending on the testing service provider, the employer, and a negative or positive result.

Hair samples are washed thoroughly to remove external contamination (residue from smoke and other substances), and cut-off levels are established to help prevent positive results from passive inhalation (second-hand smoke). However, washing, shampooing, or treating the hair will not remove traces of drugs within the hair, nor will it cover them up.

Alcohol Testing Methods And Details:

Alcohol is normally detectable with a breathalyzer for up to 12-24 hours. Rule of thumb is that a body will typically burn an ounce of alcohol, i.e. one shot or one beer, per hour. A person's BAC is determined by factors such as body size and weight, metabolism rate, food intake, and type and amount of alcohol consumed. These times should be considered general guidelines rather than absolutes.

Alcohol testing will normally be performed using a DOT-approved breathalyzer device (Evidential Breath Testing device, or EBT).

A positive test for alcohol concentration of more than 0.02 in the system will be confirmed by waiting 15 minutes and re-testing. A confirmation test showing less than 0.02 BAC will require no further action, while a test at 0.02 BAC or more will be reported to the employer.

In some cases, a driver's blood alcohol concentration (BAC) may be checked by testing saliva, instead.

A positive test of 0.02 will require that a driver be off-duty for at least 24 hours, and a level of 0.04 or greater will require a CDL holder to be placed out-of-service until completion of the return-to-duty process.

More Information On DOT Drug and Alcohol Testing Procedures


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.


Compliance, Safety, Accountability (CSA)

The CSA is a Federal Motor Carrier Safety Administration (FMCSA) initiative to improve large truck and bus safety and ultimately reduce crashes, injuries, and fatalities that are related to commercial motor vehicle


Federal Motor Carrier Safety Administration

The FMCSA was established within the Department of Transportation on January 1, 2000. Their primary mission is to prevent commercial motor vehicle-related fatalities and injuries.

What Does The FMCSA Do?

  • Commercial Drivers' Licenses
  • Data and Analysis
  • Regulatory Compliance and Enforcement
  • Research and Technology
  • Safety Assistance
  • Support and Information Sharing


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.


Body mass index (BMI)

BMI is a formula that uses weight and height to estimate body fat. For most people, BMI provides a reasonable estimate of body fat. The BMI's biggest weakness is that it doesn't consider individual factors such as bone or muscle mass. BMI may:

  • Underestimate body fat for older adults or other people with low muscle mass
  • Overestimate body fat for people who are very muscular and physically fit

It's quite common, especially for men, to fall into the "overweight" category if you happen to be stronger than average. If you're pretty strong but in good shape then pay no attention.


Dispatcher, Fleet Manager, Driver Manager

The primary person a driver communicates with at his/her company. A dispatcher can play many roles, depending on the company's structure. Dispatchers may assign freight, file requests for home time, relay messages between the driver and management, inform customer service of any delays, change appointment times, and report information to the load planners.


Hours Of Service

HOS refers to the logbook hours of service regulations.


Operating While Intoxicated


When a violation by either a driver or company is confirmed, an out-of-service order removes either the driver or the vehicle from the roadway until the violation is corrected.

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