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Testing reasons

Reasons for drug testing

Combining one or more reasons for testing is the best way to avoid hiring drug-using applicants while discouraging substance abuse among employees.

Drug testing programs aim to filter out drug users and deter drug use in the workplace. Since companies first began drug testing their employees in the 1980s, drug use among workers subject to testing has steadily declined.

Understanding when to test is directly linked to which drug testing solution your organization should select. Among the following reasons for drug testing, the most common are pre-employment and random.

  • Pre-employment testing helps employers to proactively protect themselves from the negative impacts of hiring drug users. Pre-employment testing is usually performed after a conditional offer of employment has been made – a negative drug test result is required before an applicant starts working.
  • Random testing, or “spot testing,” is a strong deterrent to drug users because it is conducted on an unannounced basis. Using a random selection process, (e.g., computer-generated), an employer selects one or more individuals from all the employees included in the employer’s workplace drug testing program. By using a random selection process, employers ensure that there is no bias and that all employees have an equal chance of being selected, even those who have been drug tested recently.
  • Periodic testing is scheduled and is typically performed on current employees at consistent time periods throughout the year. Many companies choose to perform annual periodic testing – especially if employees are required to undergo an annual physical.
  • Post-accident testing, sometimes referred to as “post-incident” testing, is performed after an employee has been involved in a workplace accident. Testing is used to determine whether drugs were a factor in the incident. Employers who implement post-accident drug testing must establish objective criteria for how and when testing will occur. Some examples of criteria include fatalities, injuries that required medical assistance, police citations or damage to a vehicle or property above a specified monetary amount.
  • Reasonable suspicion testing, also known as “for-cause” testing, is performed when supervisors have evidence or reasonable cause to suspect an employee of drug use. Evidence is based upon direct observation, either by a supervisor or another employee. Specific reasons for reasonable suspicion testing include physical evidence of illicit substances, patterns of erratic or abnormal behavior, disorientation or confusion and an inability to complete routine tasks.
  • Return-to-duty testing is for employees who have previously tested positive for illicit substances or violated a company’s drug and alcohol policy. For both the general U.S. workforce and the federally-mandated, safety sensitive workforce, return-to-duty drug testing is a single test that is performed at a scheduled time, typically following the completion of a drug abatement program.
  • Follow-up testing is for employees who have previously tested positive for illicit substances or violated a company’s drug and alcohol policy. It is usually performed in conjunction with return-to-duty drug testing. Follow-up testing is performed after an initial return-to-duty test, and is only completed if the employee tests negative for drugs on the return-to-duty test and returns to their position.

Drug testing can help to improve employee morale and productivity while decreasing absenteeism, accidents, downtime, turnover and theft. Because every business and workforce is unique, every employer should make a careful determination about the drug testing program elements that are most beneficial for their workplace.

Download our Drug Testing Solution At-A-Glance matrix to compare urine, instant urine, oral fluid and hair drug testing.

Get more workforce drug testing resources from Quest Diagnostics.