Drug Testing Glossary

Frequent terms and definitions used throughout Hound Labs


The degree to which the measured concentration of analyte aligns with a known reference value.

Active THC Molecule

THC is the principal psychoactive compound found in cannabis and is one of several cannabinoids produced by the cannabis plant. There are two common types of THC found in cannabis products: delta-8 and delta-9.

Delta-8 tetrahydrocannabinol (d8-THC or delta-8 THC) is a naturally produced psychoactive cannabinoid but is not found in significant amounts in cannabis plants. However, concentrated amounts of delta-8 THC can be synthetically manufactured.

Delta-9 tetrahydrocannabinol (d9-THC or delta-9 THC) is the main psychoactive cannabinoid found in cannabis.

A breath test detects active Delta-8 and Delta-9 THC molecules.


A chemical substance being identified and measured in a sample/specimen.

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Canceled Test

A drug test that is canceled due to a problem with the testing process itself. Canceled tests do not yield positive nor negative results.

Cannabidiol (CBD)

Cannabidiol, also known as CBD, is one of the two best-known compounds derived from the cannabis plant. The other is tetrahydrocannabinol, or THC, which is the psychoactive compound in cannabis.


A class of biological compounds in the cannabis plant. The main cannabinoids are THC and cannabidiol (CBD), although more than 100 other cannabinoids have been identified.

Cannabis / Marijuana / THC

Cannabis refers to all the products derived from the Cannabis sativa plant. Marijuana refers to the products from the plant that contain substantial amounts of tetrahydrocannabinol (THC). THC is the principal psychoactive compound found in cannabis and is one of several cannabinoids produced by the cannabis plant. Hound Labs often uses the terms interchangeably but will specify in some instances.

Confirmation / Confirmatory Test

In drug testing, confirmatory testing is the use of definitive technology to specifically identify and quantify a drug or its metabolite. A confirmation test is often performed as a secondary test that occurs after the screening test.

Chain of Custody

Chain of custody refers to the documentation trail of the collection, testing, and analysis of a sample and is commonly used in both workplace and criminal justice testing. It is the chronological documentation of the sequence of custody, the transfer, control, analysis, and disposal of any physical or electronic evidence of a drug test.

Chain of Custody Form

The chain of custody of any particular sample is documented on a Chain of Custody Form (COC) or Custody and Control Form (CCF). Hound Labs utilizes a paperless version commonly referred to as an electronic Chain of Custody Form (eCCF or eChain) to facilitate an automated exchange of data, faster turnaround times, and reliable results for our customers.

Collection Site / Clinic

A drug testing collection facility where donors present themselves for the purpose of providing a sample.


A qualified technician who runs an approved sample collection protocol, offers guidance and assistance to those providing a sample for testing.

Cutoff Level

The minimum quantity of a drug analyte needed for a test result to be rendered non-negative. A Hound Labs sponsored study conducted by a reference lab under Institutional Review Board-approved protocol found that the confirmed cut off for the HOUND® CANNABIS BREATHALYZER screening and confirmation assay is 20pg/mL.

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Designated Employer Representative (DER)

An employee authorized by the employer to take immediate action to remove any employee from safety-sensitive duties and make decisions regarding further testing and evaluation processes.

Detection Window

In drug testing, the period of time after use that a drug may be detected at or above a specified cutoff level. 

Donor / Employee / Applicant

A donor is an employee or job applicant who is presenting themselves to a collection site for the purpose of submitting to a drug test.

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Employee Assistance Program (EAP)

Third party organizations contracted with employers that provide educational and counseling services. Types of services and who may be eligible varies and will be detailed as part of employee benefit packages.

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The deterioration of an individual’s judgment and/or physical ability impacts their ability to function productively and/or safely. Such things as drug or alcohol use, sleep deprivation, or distraction could all be impairing.

Impairment Standard

Often referred to as a “per se” limit, a legal impairment standard indicates that someone who is over a cutoff level of a substance can be considered impaired even if it cannot be proven that the person is experiencing potentially negative effects. With alcohol, this is referred to as a Blood Alcohol Concentration (BAC) and a person can be found guilty of operating a vehicle if they are over the per se limit of 0.08% or higher (only Utah has a different BAC level).

There is no impairment standard for cannabis. There are no drug tests that prove impairment and there are no levels of impairment for any drugs that are used in workplace testing.

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A drug test where the sample is sent to a laboratory for processing; results often take multiple days to process.

Limit of Quantification (Sensitivity)

Synonymous with sensitivity; smallest amount of analyte that can be reliably measured.

Liquid Chromatography Mass Spectrometry (LC-MS)

Analytical tool that involves the physical separation of analytes in a complex sample/specimen (through liquid chromatography) followed by their mass-based detection and quantification (using mass spectrometry).

In liquid chromatography, the specimen is dissolved in a fluid called the mobile phase, which carries it through a system on which a material called the stationary phase is fixed. Varying interactions, with the stationary phase, of the different specimen constituents leads to their physical separation. Hence, a complex specimen is simplified to enable more accurate detection of the analyte of interest.

Mass spectrometry allows the measurement of the mass-to-charge ratio (m/z) of one or more molecules present in a sample. These measurements are used to accurately calculate the exact molecular weight, and identify the presence of an analyte, its purity, and quantity using very small amounts of input sample. It is valuable for use in identifying the chemical makeup of complex substances.

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Medical Review Officer (MRO)

A licensed physician who is responsible for receiving and reviewing laboratory results generated by an employer’s drug testing program and evaluating the potential medical explanations for certain drug test results.

Metabolize / Metabolite

Drug metabolism refers to the process by which the body modifies a drug’s chemical structure to enhance or reduce its effect and/or eliminate or retain it. This process results in chemical byproducts called metabolites, which are the chemicals some drug screens test for.

Urine- and hair-based testing detects inactive metabolites.

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Negative (Drug Test)

A sample in which the presence of a drug or metabolite is below the designated cutoff.

Non-negative (Drug Test)

A sample with a drug/drug metabolite concentration greater than or equal to the designated cutoff level. In two-tiered testing, such screening results are ‘presumptive’ and lab-based confirmatory testing is typically performed.

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The degree of variation in measurements of the same specimen due to system uncertainties.

Psychoactive (Drug / Substance)

Substances that after being consumed (taken into the human body), affect mental processes – e.g., perception, consciousness, cognition, or mood and emotions.

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Recent Use

For cannabis testing purposes, this refers to tests designed to detect “workday” or “proximate” use that occurred within a few minutes or hours prior to sample collection.

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Safety and Security-sensitive Positions

In drug testing, a safety-sensitive role is a job where the effects of drugs or alcohol could negatively impact someone’s health and safety, or result in injury to an employee, coworker, contractor, the public, or the environment.

A security or business-sensitive role is a job involving finances, data, valuable commodities, firearms, and property management where the workday use of drugs may undermine the interests of the company and increase risks toward others.

Sample / Specimen

The biological output that is presented for testing. In drug testing this typically refers to breath, oral fluid, urine, or hair.

Screening Test

The initial laboratory analysis performed in a two-tiered testing process. The screening test checks for the presence of a drug or metabolite and yields a negative or presumptive non-negative result. Negative results are removed from further analysis and non-negative results move to confirmatory testing.



The ability of an assay to detect a specific analyte of interest, rather than other compounds in the specimen.

Stand Down

A situation where an employee is required to excuse themselves from job duties and responsibilities that entail the use of materials and operation of machines that would create an unsafe working environment if the employee has reduced judgment after using alcohol, drugs, or other substances. This situation arises when an employee is being evaluated or a drug test has yielded a non-negative result.

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Tamper-evident / Tamper-resistant

A product that is tamper-evident is designed to reveal any interference with contents and a tamper-resistant product is designed to be difficult to interfered with. The goal of these design elements is to reduce cheating and limit adulterated samples.

Our cannabis breath test has been designed with both these design elements in mind.


Third Party Administrator (TPA) / Consumer Reporting Agency (CRA )/ Reseller

An organization that provides direct and administrative services to help an employer or other organization manage a workplace drug testing program. Related to cannabis breath testing, resellers create a network of organizations that buy and resell testing services to their employer clients.

Two-tiered Testing

Workplace drug testing best practices involve two-tiered testing – an initial screen on one sample, followed by a confirmatory test on a second portion of the same sample. The initial test is intended to remove negative samples from further consideration.

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United States Department of Transportation Drug Test

A drug test completed under DOT authority on a DOT-regulated employee.

Employees Are Worth Keeping

Don’t risk losing them by using outdated cannabis tests