HEPA is simply one step for providing clean air, I personally don't use carbon since I don't have to care about smell. ;)

There are significant differences required to grow "CLEAN" cannabis. There isn't any "extra clean" the standards of your state allow significant contamination. Their standards are a joke compared to reality and cannabis. What you're using is so far from clean it's ridiculous. One gram of any strain I grow will overpower all smells in any dispensary I've ever been in. Dispensaries are growing garbage. Without knowing what truly clean cannabis is, you'll never notice they're selling you such low quality.

Looks like you're going to stick to your ignorance and play the fool. Have fun reading this again in 20+ years when you FINALLY come across clean cannabis. :)