An Ignition Interlock Device cannot detect marijuana
Now that pot has been legalized for recreational or medical purposes, “Can An Ignition Interlock Device Detect Pot?” is a question that comes up often.
Your Ignition Interlock Device is specifically designed to detect and measure your breath alcohol content. However, while it can’t be measured, blowing marijuana smoke into the Ignition Interlock Device could register as a violation. It could force you to retest, or even cause damage to the Ignition Interlock Device (IID).
Most Ignition Interlock Devices have a sensor inside that is designed to detect any amount of alcohol in one’s breath sample. Since pot doesn’t contain alcohol, an Ignition Interlock Device is not technically designed to detect marijuana.
However, we strongly discourage smoking pot (or using certain prescription medications) during your restricted driving period—especially smoking while you’re driving. That’s true even if you live in a state where marijuana or pot has been legalized, or is used for medicinal purposes. We do not encourage or condone any illegal activity related to the recreational or medicinal use of pot, marijuana, weed, or any other form of THC.
Also, be sure to rinse your mouth out with water before taking a breath test with your Ignition Interlock Device (IID). Particles left in the mouth from smoking pot or marijuana may litter, damage, or otherwise deter your device from allowing you to complete and pass a breath test.
