A superior design would be a tax based on volume, as volume is a better proxy for the harm associated with consumption (the negative externalityAn externality, in economic terms, is a side effect or consequence of an activity that is not reflected in the cost of that activity, and not primarily borne by those directly involved in said activity
For the study, then, Shields and his co-authors reviewed hundreds of published scientific papers, including human studies, animal studies and smoking machine studies
If you prefer smaller, fresher hits without waste, packs win
Smoking can also damage the lining of the blood vessels which directly affects blood flow
Ensure that the device is turned off or otherwise protected from unwanted activation