Fail a drug test from second hand smoke?

My obgyn office does a drug test at 28 weeks. I do not smoke and haven't smoked marijuana since before I was pregnant. My husband on the other hand does (it is legal where I live) he usually doesn't smoke it around me but sometimes we will watch tv together and he will. He is stopping before our son is born because he doesn't find it appropriate to smoke in front of children and he is getting tired of it making him so lazy. 
Anyways, was curious the possibility of it showing up in my urine? I told my midwife my husband smokes but I don't, I told her I didn't want to be called a liar if my test came back psotive because of possibly somehow inhaling enough to trigger a positive result. 
Curious if anyone else has gone through this?
I know I will get a ton of judgemental remarks. My husband is a good hard working man and he just enjoys relaxing just like people do with alcohol or a cigarette. But I guess to a lot of people those things are SO different.  Lol