Frequently Asked Questions

Employer Drug Testing

Yes. The drug and alcohol testing that occurs in a workplace depends on the employer's drug-free workplace policy. For businesses that must be compliant with the Department of Transportation (DOT), the DOT — along with the specific agency the business works under — will require particular testing. 

Yes, there are no State or Federal laws prohibiting drug testing after an offer of employment is made.

Not a good idea from a liability prospective.  Just think about what you will do if the person tests positive.  Your best practice and to be safe from liability is to have a drug free workplace policy prior to drug testing employees. Custom written drug testing policies are available from US Drug Test Centers.

You have to have a reasonable suspicion to drug test an employee who you think is under the influence of drugs or alcohol.  This reasonable suspicion should be documented and made by a supervisor who has received supervisor training on signs and symptoms of someone whom may be under the influence of drugs or alcohol.  This training is available from US Drug Test Centers.

DOT covered employees are those that work in a DOT safety sensitive position and defined by the DOT Agency that regulates your business.  There is a tool that you can use to determine this and it will help you make the decision as to which employees are DOT.  Click Here for this tool.  You can also call US Drug Test Centers for assistance.

You should have a company drug free workplace policy stating the consequences of a positive drug test.  You can fire an employee for a violation of your company policy.  It is not a best practice to fire someone based on suspicion of drug use.  Always check with your human resources and/or legal departments.

If you reasonably suspect an employee of being intoxicated or impaired by drug use, why would you let them driver a car or your company vehicle?  Safety is your priority.  If you are requiring the employee to take a drug test either call out a mobile collector or take the employee to the drug test center.  Do not let the employee drive.  Yes, an employer can be responsible for something that happens on the road when allowing an employee to drive after suspecting drug or alcohol use.

DOT covered drivers are required to have a negative pre-employment test for DOT prior to operating in the safety sensitive position.  Failure to have this negative pre-employment test will place the carrier out of compliance which can result in a monetary fine or perhaps being placed out of service. If you have drivers with no negative pre-employment test; get them tested immediately even if they have been with you for many years.

Yes, with medical and recreational marijuana, employers still need to maintain drug free workplace programs. Various federal laws require all employers to provide a safe and healthy work environment and those with certain safety-sensitive jobs or who have federal contracts or grants to maintain a drug-free workplace. Employers whose businesses are related to public safety and security must be able to ensure their employees are not impaired while at work. Otherwise, employers face litigation of a different sort: lawsuits caused by impaired employees that involve injuries or deaths among fellow employees or the general public.

In States with medical and/or recreational marijuana, employers may choose whether to make an exception for medical marijuana use.  But, if that is an exception that an employer decides to make, it must be an exception that is applied after a thoughtful consideration of all the safety and business risks involved and done in a manner in which the employer does not unnecessarily expose itself to potential claims for discrimination (particularly if the exception is granted to some but not all employees).

Yes, very much so.  Employees who test positive for marijuana have 55 percent more industrial accidents, 85 percent more injuries, and absenteeism rates that are 75 percent higher than those who test negative on a pre-employment exam. "1" The National Institute on Drug Abuse has cited several studies linking employee marijuana use with “increased absences, tardiness, accidents, workers’ compensation claims, and job turnover.”2"  


"1" Abbie Crites-Leoni, Medicinal Use of Marijuana: Is the Debate a Smoke Screen for Movement Toward Legalization? 19 J. Legal Med. 273, 280 (1998) (citing Schwartz, et al., Short- Term Memory Impairment in Cannabis-Dependent Adolescents, 143 Am. J. Dis. Child. 1214 (1989). 

"2" National Institute on Drug Abuse (NIDA). (2011). Research Report Series: Cannabis Abuse. Accessed November 2014. 


Usually the answer is no.  At US Drug Test Centers we use a medical review officer (MRO) to review each drug test and verify the results. If a positive test result comes back the MRO will contact you, the donor who provided the specimen and discuss the positive result along with any medications you may be taking.  The MRO will check with your prescribing doctor or pharmacy to verify any prescriptions you reported and then report your drug test result back out your employer as a negative drug test result. The MRO acts as an impartial and independent advocate for the integrity and accuracy of the drug testing process.

General Questions

This depends on the company's drug-free workplace policy and the drug test panel(s) they've chosen. The most basic testing typically screens for marijuana, opiates, cocaine, and methamphetamine. However, panels can be created to test for as many substances as an employer wants.
You can get drug tested with a urine or hair sample. When the sample is screened, it's looking for the presence of drugs (including certain prescription drugs) and alcohol, which can be detected in your body for several months. Drug testing is painless and quick.
DOT drug testing is the drug and alcohol testing required by the Department of Transportation for its individual agencies. This testing is mandatory for safety-sensitive employees to keep the public and other workers safe.

Dilute means the urine specimen had more water then urine.  This basically means that the donor consumed a large quantity of water before providing the urine specimen. Maybe the person drinks a lot of water, maybe they drank a lot of water on purpose in order to try and cheat on the test.  A positive dilute is still a positive result.  With a negative dilute result there may be suspicion.  This is not a positive.  Employers should have a provision in the drug free workplace policy for negative dilute results.  This policy can state that the negative dilute is accepted as negative or that the employer requires the person to go back for another test.  The individual going back for another test should be instructed to not drink any large quantity of water prior to this next test, perhaps even a supervisor should accompany the person for the second test.

US Drug Test Centers has over 20,000 collection sites nationwide to serve you. Most of our locations are able to provide urine, hair and breath alcohol testing however, some locations do not offer all services. Most of our locations accept online orders and are "in network" however, in order to provide more availability in the United States we offer access to locations that are "out of network" meaning they are still able to provide the services but there is an additional fee.

There is no exact science for this and may depend on hair testing, oral fluid testing or urine drug testing.  For hair testing it takes about a week.  For oral fluid drug testing it can be just a few hours.  For urine testing it can be from 4-5 to 8-12 hours.  The exact time can be different from one individual to another and a lot of other are factors involved including which drug, how strong the drug is, the person’s metabolism, the persons weight and perhaps what the person has eaten or drank.  Bottom line is if the individual uses illicit drugs, they will at some point show up in hair, oral fluid or urine. 

Specimens tested at a laboratory are screened using immunoassay. An immunoassay is a test that uses antibodies to detect the presence of drugs and other substances in urine.  There are cut-off levels that determine if this screen is negative or positive.  If above the cutoff level the specimen goes to Gas Chromatography Mass Spectrometry (GC-MS) testing to pinpoint the exact metabolite of an illegal drug in the urine specimen at a specific quantitative level.  If the GC-MS is above the confirmation cut off level the test is positive for the specific drug identified.  

For court it is best to have a laboratory based test with a review by an MRO.  An instant test is reliable for a negative result but not reliable for a positive result.  If the result of an instant test is not negative, the specimen should be sent to the laboratory for additional testing specifically Gas Chromatography Mass Spectrometry (GC-MS) testing to pinpoint the exact metabolite of an illegal drug in the urine specimen at a specific quantitative level.  Without lab confirmation testing and MRO review, a positive test may not stand up in court.

Typically no one will watch you provide a urine specimen, this is done in private.  Based on DOT regulations or Company policy some tests such as return to duty and follow-up will be direct observed tests which means the same sex collector will observe your urination.  Also if your urine specimen temperature is out of range or if the collector finds something suspicious; a second collection will be completed with a same sex collector observing your urination. Less than five percent of all tests require the direct observation.

The laboratory that tests your specimen will send your test results to a Medical Review Officer (MRO) and if your result is positive the MRO will call you regarding your test result.  The MRO will discuss with you any possible medication you are taking which could affect the outcome of the drug test.  If there is a prescription the MRO will ask for the prescription information and pharmacy and verify this.  If everything checks out your test result will have a final result of negative.

We ship our drug testing specimens overnight to our laboratory. Those that come back negative are generally reported the next business day. A positive result may cause a delay in the final report so that a medical review officer can review the results and confirm the accuracy. Most results are received within a few days time.

Individual Drug Testing

Drug testing specialists indeed look for clear markers that urine is synthetic. For instance, if the pH level, specific gravity, levels of nitrite, or temperature are off, it's a warning sign. 
Yes. Alcohol can be detected for 3-5 days in urine and approximately 90 days in hair (although it depends on the length of the hair sample). The best way to detect current alcohol impairment is with a breath alcohol test. 
Bigger companies, like General Electric, often drug test — although the size of the company certainly is not the only indication. Check with a company's drug-free workplace policy (along with local/state laws) to know for sure.
This depends on your state's laws, and whether or not they consider drug testing kits "drug paraphernalia." You should also check the test to see what it contains and how it works. Bear in mind that even if it's legal, a test might not be accurate. 

You drug test results will not be released to anyone else unless you provide you consent to do so.  Sometimes for example our customers order a drug test for probation and ask us to send the results to their probation officer.  Everything is confidential in the drug testing process.  Only with your consent will your results be send to other parties.  The only exception is with a subpoena or court order.

This depends on what specimen is being tested – hair, oral fluid or urine.  Urine will detect drugs in your system for up to 3 – 4 days.  Hair goes back up to 90 days and oral fluid testing goes back 1 – 2 days.  It is not an exact science so if you use drugs, you may test positive on a test no matter how long you wait.   

No, the lab is testing what is inside the strands of hair.  Not the outside of the hair.  When you ingest drugs, it goes into the hair follicle, and then into the strands themselves.  Shampoos and dyes will not affect the hair test. 

A Medical Review Officer (MRO) is a licensed physician who reviews and verifies drug test results.  The MRO determines if a legally prescribed drug effects your drug test result.  You may be called when you have a positive drug test.  You may also be called if your legally prescribed medications effect your drug test result.  The MRO will verify your prescription and once verified your result will be reported as negative.

Typically you need an order form for the drug test or a paper chain of custody form (CCF).  You also need your government issued ID – a driver’s license.  If you are going for a hair test you need hair on your head or on your body. If you are going for a urine drug test do not drink an excessive quantity of fluids, this can cause a dilute specimen.  With a dilute specimen you may have to go back for another test.

Neither is better than the other.  It depends on what you are trying to accomplish and why you are taking a drug test.  Urine will detect drugs in the system for up to 3 – 4 days and is less expensive.  Hair will detect drugs in the system for up to 90 days and is more expensive. Click Here for more on urine hair test panels.  Click Here for more on hair test panels.  

This really depends on what you are trying to accomplish and why you are taking a drug test.  Is it required for employment, probation, court ordered or other requirements?  If yes, you should ask what test is required.  It could be a urine specimen, hair specimen or oral fluid specimen.  It could be a 5 panel test, 10 panel test, alcohol test or many others.  The most popular test ordered is a 5 panel urine test.

An oral drug test will only detect drug use that occurred within the last 1 or 2 days. This type of test can detect drug use within the first four to five hours which would be missed with a hair or urine test.

A urine drug test will detect drug use that occurred within the last 1 to 4 days.

A hair drug test will detect drug use that occurred up to 3 months prior to testing but will miss any drug use that occurred 7-10 days prior to testing.

With oral and hair drug tests the collection of the specimen can be directly observed whereas with a urine test the donor has privacy when the specimen is collected. This means that it is harder for a donor to cheat when taking an oral or hair drug test.

As you can see, each type of drug test has benefits. We will help you to determine which test best suits your needs.