As of 2015, many employers in the United States, especially those who are hiring for positions in the railway, airline and federal transportation industries, require pre-employment or work-related drug testing to find out if applicants or current employees are using certain drugs. Workplace drug testing is particularly essential for companies that prioritize public safety. Drug testing involves obtaining a biological sample, such as blood or urine, to assess the presence of certain drugs in the body.
Employers usually order drug tests if an employee's safety in the workplace may be compromised in the event an impairment of judgment or physical skills occurs due to drug or alcohol abuse. They seek to maintain high productivity and fewer occurrences of drug abuse in the workplace. Work-related drug tests target commonly used drugs, including marijuana, cocaine, opiates, alcohol and prescription drugs.
Applicants generally undergo pre-employment drug tests by providing a urine sample. In some cases, they provide blood, hair, sweat or saliva samples. Work-related accidents may lead to directed testing, and jobs that require high safety levels may require random drug testing. Employers who suspect drug abuse an employee of drug abuse may also conduct a drug screening.
The first part of a drug screening program is an initial or immunoassay testing method. If the test reveals a positive result, the screening program proceeds to a confirmatory gas chromatography-mass spectrometry method to determine the specific drug substances and their amounts.