Hair drug testing provides a longer detection window for drugs of abuse. A standard hair drug test uses a 1 ½ inch sample of hair, which provides an approximate 3 month history of drug use.
While urinalysis and oral fluid drug testing measure relatively recent use (2-3 days for most drugs), hair drug testing can detect drug abuse as far back as 90 days. Here are some key points to consider as an employer:
- For pre-employment drug testing, many clients will conduct both a hair drug test (for longer-term history) and an urine drug test (for recent history) for applicants
- Hair drug testing is less invasive and harder for the donor to “cheat” the test
- Positive rates for hair drug tests are typically four to five times higher compared to those of urine drug tests
- Hair drug testing is not recommended for reasonable suspicion or post-accident testing circumstances as a hair drug test would be ineffective because it doesn’t detect recent use
How We Can Help
Learn how we can help implement and manage a hair drug testing program.