These are some tips that anyone who is taking a hair test should know. A cousin of mine works for Quest Diagnostics and literally handed me the business on hair testing. My cousin has been performing clinical testing on hair for 8 years now. She is licensed and a veteran in the business, so I trust her word, despite what you and I think we know, she does this every day. She told me a lot of things that are contrary to what I have read online...but were nonetheless, very useful things to know. So here it is, straight from the Lab technicians mouth.... Testing Varies Between Laboratories Psychemedics, Quest Diagnostics, Omega Labs....These companies and their testing procedure vary. This has a lot to with your chances for passing. For example...Quest Diagnostics employs EIA testing which is a less accurate form of testing. Psychemedics uses ELISA testing which isolates the drug metabolites, and is far more accurate. Still others use GC/MS or gas chromatography/mass spectrometry, which is also a less accurate form of testing. Look it up for details. Basically, your chances for success start here with the facility and their methods. Which Drugs Have you Been Using and how much? Hair testing is primarily used for the detection of illicit drugs (Meth, cocaine, heroin, PCP, ect.) If you have been using illicit drugs, your chances of passing are slim to none. Cocaine, meth, and PCP bind strongly and in clusters to the users hair follicle and can be found within days after use and for up to 3 years after use, no shit. Pot is a different story. To my surprise, the THC metabolites are actually hard to detect through hair testing because THC metabolites do not bind the the hair follicle easily. Tobacco, Hookah, and users of synthetic pot (K2, incense, ect) have a greater chance at passing for THC because these toxins chemical make up is very simular to that of THC and dilute the hair follicle thus making THC harder to find. Also, she described that recent research also indicates that exposure to high humidity will rapidly break down marijuana metabolite levels in the hair...which I thought was very interesting. Finally, regardless of your level of usage of any drug, you are not safe from a positive result. Everyone is Different Your age, weight, height, and drug usage mean ABSOLUTELY nothing when it comes to hair testing. You can be a heavy, moderate, or light user of THC and your chances of passing are not very different as the next guys. HOWEVER, your hair type and your Metabolism DO MATTER. The thicker and darker your hair, the less chance you have of beating the test. Hair can be sampled from anywhere on the body, but body hair has been PROVEN to be a more difficult sample to process, as it does not accurately display usage history like the hair from your head does. My cousin told me that samples taken from the leg test negative FAR more often than samples from the crown of your head. Lastly, your metabolism is your only weapon in the fight against a positive result. This is truely Dawinism at its finest. The Best Way to Pass Your Test If you are taking your test in 3 or more weeks from now, Detox your body immediately. It does not matter when you stop smoking, THC will continue to grow into your hair for as long as it is in your system. This is where most people go wrong and believe that washing their hair with various methods day after day after day will render them clean, which is NOT the case...it will only begin to toxify again as the hair follicle continues to grow. The day your blood is free of THC is the day your hair will stop growing with THC in it. At this point she recommends cutting your hair...its the only 100% sure way to test negative...and that's only if you have the time to grow 1.5 centimeters back before the test. Unfortunately, there are no ways to detox your hair...as much as you, Macujo, Mac, or anyone else and their method tells you it can be done. If you dont believe me look it up...and see the posts here that will prove that. In fact, all these methods do is cause extreme damage to your hair and scalp. Im seriously not trying to discourage you or talk shit to these guys or call anyone a liar...but it is scientifically not possible to remove toxins from your hair once they are there. In fact you're more likely to default (fail) your test because they will find the adulterants in your hair. Seriously, Call the lab and ask for yourself. She laughed as she described the volume of individuals who come in with dyed/bleached hair, smelling of vinigar and tide. HERES THE KICKER and quite possibly the most important part of this thread. There are products that act as masking agents. Yes it is true they wash your sample before it is tested, HOWEVER there are products available that are proven to penetrate the hair shaft and furthermore mask individual metabolites within your hair follicle. This is NOT THE SAME THING as a masking film around the hair itself. Her lab is aware of these products and their inability to detect them, they simply choose to not employ more costly testing procedures, THATS THE ONLY DIFFERENCE and the only reason they work...for now. She goes on to tell me that it is because the labs enzymes (acting agents) can not break down the masking chemical through EIA testing that they can not identify the drug metabolites. She emphasized that this has everything to do with their method of testing...remember EIA and ELISA? These products will not work with ELISA testing. I have been reading and researching all that I can about this topic, because I recently had to take a hair test. I know the feeling of dread that overcomes when you find out you have to take one and know your using...believe me. When I found out my cousin had been performing these kinds of tests...I immediately demanded she give me the down low on it. This is what she told me...so please, save your negative or rude comments...I'm posting this to help YOU be more knowledgeable and make a better decision for yourself. So there it is. Good Day to you.