Smoker taxi driver should be made easily identifiable

There should be a tag or sticker to identify taxi whereby the drivers smoke. Taxi made easily identifiable would be useful to passengers who are asthmatic, allergic to chemicals derived from cigarettes, pregnant ladies who are health conscious, families traveling with babies (and concerned about the thousands of chemicals in cigarettes), and people who would prefer "fresh air" in the air-conditioned taxi. It is really unbearable to be confined in an air-con vehicle with strong scent of cigarette smoke. Worst are those taxi drivers who smoke inside the car, thus leaving an unbearable cigarette smell.
-
Why am I writing about this?

-

For parents with children who are car sick, having them endure a trip in a cigarette-smoke choked taxi is a torture. Worst is when the smoker taxi driver was unwilling to let passengers to unwind the car window. I have came across this taxi driver and when we told him that our kid is car sick and requested to unwind the window, his reply was this,  "No. You can use plastic bag instead". With that response, we quickly requested that he stop his car. We opted to get out of his car this time rather than have our kid endure his inconsiderate attitude and smell.
-
Sometimes I think that the Transport authority or Health authority should ban taxi drivers from smoking inside their cars. This is crucial for passengers who are sensitive, asthmatic, allergic, and also those who travel with babies. If it could be helped, I wouldn't want taxis with strong cigarette odor to stop by maternity hospitals to take passengers. Sorry, it is just too unacceptable to let my baby endure the lingering cigarette smoke during our travel.
-
Having said that, I am still appreciative of taxi drivers who let passengers like me to unwind their car windows when requested. Their thoughts make our baby's journey comfortable without risk of puking (or sneezing). 

-

Just a thought.