Q. When finishing the tefilah (after maariv during Chanukah), the last one to leave extinguishes the lights of the menorah before a half an hour of being lit has passed, as they do in many Shuln that I know, is that OK?
A. Some Poiskim maintain that in a shul you do not need to leave the candles lit for a half an hour, it suffices for them to be on as long as the mispaleleim are there. It is different from a private dwelling were the publicizing is done for the people in the street and originally when this mitzvah was established, they were there for a half an hour. (Binyan Av p.46, Leket Hachanuka p. 183, Rivavos Efraim 59) Others agree in principle with the above, but suggest that lekatchila, on the onset one should put enough oil and if possible maintain them lit for a half an hour (Teshuvos Vehanhogos 4: 171,Yalkut Yosef, Moadim p.203, Netzach Yosef p.160). Melamed Lehoil (1: 121) adds that you may complete the missing time by kindling in the morning during shacharis. Other Poiskim are more stringent and permit extinguishing the lights only when there is a fire danger or other significant need. (Shevet Halevy 8: 156,)
Horav Shlomo Miller's Shlit"a opinion is that if possible one should maintain them on for the full half an hour, however if no one is going to be there you may put out the lights or at least leave one on.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit"a