Superfly, not sure about the smoking requirements, BUT, if they do have any, probably for good reason as I found out personally.
Last physical, non AME, private doctor, the subject of smoking came up again, had been thinking about quitting, was doing 3 packs a day and not feeling all that great. Doc mentions results of blood test. Elevated red blood count caused by something with a long name. Reason in plain english, several years of heavy smoking reduced lung capacity, ability of the lungs to process oxygen. Blood making up for it by manufactuing more red blood cells, eventually would have to go and be "drained" of blood regularly if level got too high.
Now for aviation, think of the side affect. If at sea level, my lungs are processing the same amount of oxygen to the blood as say maybe a normal person at 10,000 feet, what the hell would happen if I flew non-oxygen at 95000 feet. Probably mild hypoxia. Since most pressurized aircraft I believe pressurize to about 8,000 feet, then I still wouldn't be safe without supplemental oxygen probably.
Bottom line is grounded myself, did an extensive stop smoking plan in my case using non-flight-approved meds. Probably will take a couple of years for lungs to get somewhat back to normal, as it is no wing flapping for another 6-8 months. Luckily only PPL, any further plans on hold.
So, do yourself a favor, knock off the smokes, it ain't easy by a long shot, but health is a big issue here and a lack of it is very costly.