The number of shophar-blowings on Rosh Hashanah
Question
On Rosh Hashanah I volunteer to blow the shophar for the infirm and the elderly who are housebound and can’t go to the synagogue. How many times do I have to blow in each house?
Answer
Every person is obligated to hear three sets of blowing tekia-terua-tekia. Since we don’t know, what is the “terua” mentioned in the Torah, we blow three sets of tekia-svarim-terua-tekia, three sets of tekia-svarim-tekia, and three sets of tekia-terua-tekia, thirty blowings overall.
There are opinions that those who blow the shophar in hospitals, old age homes, etc., since they end up blowing very many times, should just do ten blowings each time: one tekia-svarim-terua-tekia, one tekia-svarim-tekia, and one tekia-terua-tekia.
Source
Shulchan Oruch, section Orach Chaim, ch. 590, §1