Use someones clean urine or get Quick Fix 4.0
They do test to make sure it is human urine.
Make sure if you us a substitute its at temp. 90-100 degree's
Use a 2 OZ trial size shampoo bottle or something you can put in your crotch of your undies.you can buy hand warmers at Wal-Mart or a Sporting good store for less then a buck and will keep it at temp up to 8 hours.A lab can not frisk you.They will make you empty your pockets take off hats ect.You also have the right to privacy so you will go into a room by yourself.They do color the water in the toilet Blue and turn off the water in any sink.And chances are they will listen so if your subing practice doing so quietly.They also check for detoxins and dilution.
I posted this but I'll paste it for you again.
Read the following:

What is Adulteration?
Adulteration is the tampering of a urine specimen with the intention of altering the test results.The use of adulterants can cause false negative results in drug tests by either interfering with the screening test and or destroying the drug present in the urine.Dilution may also be employed in an attempt to produce false negative drug test results.
One of the best ways to test for adulteration or dilution is to determine certain urinary characteristics such as Creatinine,pH,and Specific Gravity and to detect the presence of glutaraldehyde, nitrite and oxidants/pyridinium chlorochromate (PCC) in urine.

>Creatinine is a waste product of creatine; an amino-acid contained in muscle tissue and found in urine.A person may attempt to foil a test by drinking excessive amounts of water or diuretics such as herbal teas to "flush" the system.
Creatinine and specific gravity are two ways to check for dilution and flushing.Which are the most common used in an attempt to circumvent drug testing.Low Creatinine and Specific Gravity may indicate dilute urine.
The Absence of Creatinine (<5mg/dl) is indicayive of a specimen not consistent with human urine.Normal creatinine levels are between 20 and 350 mg/dL.Under rare conditions,certain kidney diseases may show dilute urine.

>Specific Gravity tests for sample dilution.The normal range is from 1.003-1.030.
Values outside this range may be the result of dilution or Adulteration.Elevated levels of protein in urine may cause abnormally high specific gravity values.

>Nitrite test for commonly used commercial adulterants such as Klear or Whizzies.They work by oxidizing the major cannabinoid metabolite THC-COON.Positive results generally indicate the presence of an adulterant.Nitrite is not a normal component of human urine.However,nitrite found in urine may indicate urinary track infection or bacterial infections.Nitrite levels of >20 mg/dL may produce false positive glutaraldehyde results.

>Glutaraldehyde test for the presence of an aldehyde.Adulterants such as UrinAid and Clear Choice cotaines glutaraldehyde which may cause false negative screening results by disturbing the enzyme used in some immunoassay tests.
Glutaraldehyde is not normally found in urine therefore,detection of Glutaraldehyde in a urine specimen is generally an indcator of adulteration.Glutaraldehyde is not normally found in urine However certain metabolic abnormalities such as ketoacidosis (Fasting,uncontrolled diabetes or protein diets) may interfere with the test results

>pH test for the presence of acidic or alkaline adulterants in urine.Normal pH levels should be in the range of 4.0-9.0 Values outside of this range may indicate the sample has been altered.

>Oxidants/PCC (Pyridinium Chlorochromate) Test for the presence of oxidizing agents such as bleach and hydrogen peroxide.Pyridinium Chlorochromate (sold under the brand name UrineLuck) is a commonly used adulterant.Normal human urine should not contain oxidants or PCC.The presence of high levels antioxidants in false negative results for the oxidants/PCC

The Quick Fix 4.0 synthetic urine contains all of the constituents being tested in human urine, such as creatinine, ph, and specific gravity. My periodic home tests of the QF (using the Urinecheck 7 adulterant test stick) bears all of this out as proof. These same test sticks can be found at WWW.Meditests.com
http://www.detoxforless.com/pass-a-d.../fake-pee.html
BloodyRedBarron Reviewed by BloodyRedBarron on . Testing questions from a light smoker :-) Hello :) I have a few questions regarding detox kits and test kits. I knowI have a drug and alcohol test to take for a job I've been offered. If they are testing for drugs AND alcohol, what type of test would they want? A urine test or blood test? Also, the detox kits that are readily available. Are those to be used mostly the day of the test? I am a light smoker. Which means when I have a good amount of weed I usually smoke a small glass pipeful in the morning and again in the Rating: 5