It seems that a restaurant in Twilight Express is setting non-smoking times and Cassiopeia dining isn't.
I've not found explanation in English on this issue. Sorry if these are not up to date....
Twilight Express:
- Non-smoking: Car Nos. 4 (salon car), 9 and mini-salon in Car No.7.
... according to
http://www.jr-odekake.net/train/twilightexpress/compo.h...
- A service company of JR-West group says that smoking is not permitted at a restaurant in Car No.3 during the dinner times (for which reservation is needed) and the morning time.
http://www.jwfsn.com/twilight/qanda.html
Cassiopeia:
- Non-smoking: Car Nos. 1, 4, 7, 8, 9, 10, 12 (with observation lounge).
- Smoking: Car Nos. 2, 3 (dining car), 5, 6, 11.
- Composition may differ for some trains.
... according to
http://www.jrhokkaido.co.jp/train/tr016_03.html
http://www.jreast.co.jp/cassiopeia/accom/index.html
- JR-East says in the same page nothing about smoking in a dining car while saying that a lounge car became non-smoking.
http://www.jreast.co.jp/cassiopeia/accom/lounge.html
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