I’m in middle of Shemoneh Esrei and the chazan began Kedushah. What should I do?

I’m in middle of Shemoneh Esrei and the chazzan began Kedushah. What should I do?

There’s a machlokes Rishonim (a dispute among early halachic authorities) regarding what to do if one is in middle of Shemoneh Esrei (the silent Amidah prayer) and the chazan (the one leading the davening) has begun reciting Kaddish or Kedushah. Some Rishonim maintain that Shemoneh Esrei should be interrupted and one should reply with the minyan, whereas others argue against it.

The halachah codified in Shulchan Aruch is a compromise: one should pause and listen passively to Kaddish or Kedushah, thereby being yotzei (meeting one’s obligation), and proceed with reciting the Amidah upon their conclusion. Of course, this applies only if the one davening can hear all the words that the chazzan is saying, though there are those of the opinion that hearing any participant in the minyan say “Amein” or “Kadosh, kadosh” is sufficient. 

Some suggest that it’s also necessary for the chazan to have the intention to be motzi the people in such a situation. However, most poskim don’t seem to agree with this requirement. #511

https://halacha2go.com?number=511

Practical Halacha: One minute a day. By Horav Yosef Yeshaya Braun, shlita, Mara D'asra and member of the Badatz of Crown Heights.