Why you need to keep it warm?
Since initial drug screen do not typically include special test for a sample’s validity, testing staff just checks urine temperature to make sure it’s not substituted. Real human urine is warmed by the body, and it logically follows that a fresh sample should also be warm, otherwise it must have come from somewhere other than your body. That is why fake piss must be kept warm if you don’t want your sample to be rejected even before actual drug test.
How warm a sample should be?
The normal temperature of human urine ranges from 94°F to 96°F (about 35 °C). The temperature of drug test sample must be measured during first 4 minutes after it was received, as it changes depending on ambient temperature. Acceptable range is from 90°F to 100°F (32°C - 38°C), any sample with a temperature out of this range will immediately fall under suspicion.
Container cups for the samples also usually have a built-in thermometer that registers the temperature of the piss as soon as it enters the container. So while you can easily buy synthetic urine is easy enough to acquire, hiding and using it to successfully pass a drug test can prove to be more difficult.
Microwaving synthetic urine
Microwaving fake piss is by far the easiest way to bring it to the desired temperature. All you need to do is place the container with liquid into a microwave and heat it for about 10 seconds. You can use a temperature strip to check if the sample is usable. Leaving the urine in for a longer period will give it an unusually high temperature and this is where it gets tricky. You can wait for the sample to cool down a little, but know that synthetic urine can be destroyed by too much heat.
Using hand warmers
Hand warmers are small, readily available and provide an easy way to heat synthetic urine. Just place the liquid in a small container or a sealed bag, wrap the hand warmer around it and secure using a tape or an elastic band. Take note that different hand warmers work in different ways. Some get warm as quickly as they get cold in a span of a few short hours. Warmers that maintain steady heat in the 90°F to 100°F range are perfect for the job, though you might also want to pick one that will keep the heat for as long as you need it.
Own body heat
Using your own body warmth is another popular method to keep synthetic urine warm. Place the sample in a sealed plastic bag and keep required temperature by placing it near a warm body part. The body part you choose is always a matter of preference. Most men tend to use their crotch area – their inner thighs or inside their underwear. Some women prefer to use their armpits or inside their bras.