Many American companies require employees to comply with workplace drug testing policies, which vary depending on federal, state, and local laws, industry requirements, and organizational needs. The main reasons for mandating different types of drug tests include increasing absenteeism and decreased productivity due to illegal drugs, certain prescription drugs, and the presence of alcohol, as well as providing a secure working environment and attracting top talent by being transparent about testing methods. Different kinds of drug tests, such as urine testing, hair testing, oral fluid testing, breath alcohol testing, blood tests, and others, are used to identify specific substances and their detection windows. Employers conduct drug tests for various purposes, including pre-employment, post-accident, random, periodic, return-to-duty, and reasonable suspicion scenarios. Despite the varying types of tests, no type of drug testing is 100% reliable, with false positives less likely than false negatives, provided strict collection, handling, and analysis procedures are followed.