Thanks for your reply,
My house rules state:
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******* Strictly no smoking, outdoor areas included, thanks *******
I am asthmatic and even the smell of smoke on your clothing may trigger an asthma attack. Electronic cigarettes are OK.
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I'm happy for people to have electronic cigarettes. They don't bother my asthma and some of them smell quite nice.
I once had someone smoke in the outside doorway to my kitchen (directly below my bedroom) - I could actually see smoke in my bedroom! Other than that it has just been the smell on their clothing.
It looks like they will only let you cancel 3 times without penalty. This has happened to me numerous times (more than 3 times a year).
I don't think I can make it any clearer in my house rules!