Hair follicle testing tests for certain types of drugs that someone might have used in the past. Testing is typically conducted by employers or parents to determine a history of drug abuse.
Types of Drugs
The types of drugs looked for in a hair follicle test include opiates, marijuana, methamphetamines, cocaine and PCP.
Time Period
The testing period covers a 90-day time frame. This means any drugs the person might have taken should show up positive in the test results.
Location
Fifty to 70 hair strands at least 1 1/2 inches in length can be used. Hair from any part of the body can be used. Aside from scalp hair, this can also include arm and chest hairs. The entire strand, including the follicle must be used for the testing process.
Effectiveness
Hair testing is more accurate than urine testing because it can determine low-level drug usage for the previous three months and sometimes longer.
Reasons
Some employers do random drug testing on their employees to assure proper safety habits are enforced and good character traits are maintained while the person is at work. Parents can request drug testing on their child if they suspect he might be under the influence of drugs or has abused drugs in the past.
