Second hand smoke contains little if any thc and would take copious amounts to raise your level above cutoff (I'm talking like 10 blunts inside a car with the windows up). When marijuana is inhaled your lungs absorb the thc and the exhaled smoke is virtually thc free. If it makes you feel more comfortable, go to Walmart and get an at home drug test. I'm sure you'll have no trouble passing.:thumbsup: