When COVID began, choruses were feared as the most dangerous art form. Now they’re back.

Few Philadelphia music groups were more at risk during the pandemic than the choruses. Whether large, small, volunteer, professional, in churches, or in concert halls, the prospect of droplets emitting from 100 singers with every “Kyrie eleison” drove them to inactivity or onto the laborious Zoom process of recording and syncing each individual part, and with each singer in their own video compartment.

No more — but with asterisks.

Protocols abound for performances and rehearsals. However, the pandemic video presentations — with each choir member boxed into a corner on the screen — aren’t likely to continue or be missed. “I don’t want to see any one of those damn Hollywood Squares ever again,” declared Matthew Glandorf, artistic director of Choral Arts Philadelphia.

In the ultimate symbolic return, Choral Arts Philadelphia gave the live premiere of Scott Ordway’s Twenty/Twenty on Wednesday at Church of the Holy Trinity, an elegiac piece written in lockdown specifically for video with words based on entries by 100 college-age choristers who were asked to complete the sentence, “One year ago today, I did not know that ...”

Answers included, “... that I could feel so alone ... that I could not embrace a friend, or stand close to strangers. ...”

The piece had great emotional impact a year ago when it emerged on video. And that impact seems to be undiminished. “At the first rehearsal with the ensemble,” said Glandorf, “we read through the piece, and singers were breaking down. "

Composer Ordway resists taking anything close to full credit: “Each line ... has the weight of truth ... because it began as a nonfiction statement of fact.” Choral Art’s program, titled The Lost Oratorios of Giacomo Carissimi, is repeated at 4 p.m. Sunday at the Church of the Good Shepherd in Bryn Mawr and will be streamed live through choralarts.com.

This and other upcoming choral concerts represent one of many significant steps in the resurrection of choral concert life. The fact that such performances can happen at all is because the Centers for Disease Control and Prevention has declared indoor maskless vocal concerts to be safe among vaccinated singers. Masked rehearsals (often held in more confined spaces) are still encouraged.

More specific rules are found in individual venues, rehearsal halls, and even labor unions. Most Philadelphia choirs are a mix of volunteers and professionals, the exceptions being the all-professional Variant 6 and The Crossing choir. In the end, protocols are about individual comfort zones. One member of Variant 6, who has a small child at home, stays masked whenever possible.

The audience experience generally requires masks, contactless tickets, and vaccine checks. Mendelssohn Chorus’ Dec. 11 A Feast of Carols concert tends to be a family event; children under 12 are asked to provide a negative PCR test within 72 hours of the time of performance. Once customary postconcert receptions in this highly social world are becoming optional; The Crossing’s September concert held one outdoors. Singing City’s Dec. 12 concert Joy Abounds will skip the reception.

Ticket sales are sometimes limited to maintain social distancing. The Crossing kept its Presbyterian Church of Chestnut Hill to 260 out of a possible 360 in September. Mendelssohn Chorus of Philadelphia’s Dec. 11 concert at St. Paul’s Episcopal Church in Chestnut Hill limits ticket sales to 400 out of a possible 600 but added an extra, same-day performance. “Hopefully, people will be able to spread out and not feel like they are squished in,” added executive director Flo Gardner. “We’ll see how it goes!”

Inside the rehearsal room, every group is different. “A larger group means more contacts,” Crossing conductor Donald Nally observed, “and in some circumstances, greater anxiety.” His own 33-member group, thoroughly vaccinated and varying in size, continued singing over the past year but in outdoor circumstances with state-of-the-art amplification, and gradually worked back into conventional indoor concerts this past fall.

The 40-voice Choral Arts had no pushback on protocols. But the 119-voice Mendelssohn Chorus lost 10 members. The 80-voice Singing City — which rehearses in the well-ventilated Friends Center — allows the few members who either resist protocols or might be showing breakthrough infection symptoms to stay home and monitor rehearsals via Zoom. They’re welcome to sing as well, though the time lag in the technology doesn’t allow singers on each end to synchronize. Therefore, home singers can’t be heard by the rest of the choir. “But it’s keeping them engaged,” said music director Jeffrey Brillhart. “They’re staying connected.”

With the Temple University vaccination rate beyond 98%, the main priority for the various choirs is to rehearse for shorter periods and to maintain three feet of social distance, according to Paul Rardin, chair of the vocal arts department.

Extra precautions are sometimes planned shortly before performances, just to be extra safe. “We’re going to COVID test the choir the day before the concerts so we can sing without masks,” said Brillhart.

Long days and unmasked singing required by recording sessions for Variant 6′s debut album New Suns, to be released next year, went even further: “We did a week of quarantine, and then PCR tests,” reports soprano Rebecca Myers.

Yes, there’s tedium and anxiety. But time and again, members express an overriding relief for being back, so much that in some groups social distance is hard to maintain. Nally put it this way: “We’re getting back to what it is we do: Tell the stories of our time through communal singing.”

Choral Arts Philadelphia: The Lost Oratorios of Giacomo Carissimi plus Scott Ordway’s “Twenty/Twenty,” 4 p.m., Nov. 14, Church of the Good Shepherd in Rosemont. Tickets: $15-$40. Streaming: $10. Information: choralarts.com

The Crossing Choir: Motion Studies, 7 p.m., Nov. 18 at the Stotesbury Mansion in Center City and 5 p.m., Nov. 21 at Presbyterian Church of Chestnut Hill. Tickets are free with RSVP required on the 18th, $20-$35 for the 21st. Information: crossingchoir.org

Mendelssohn Chorus of Philadelphia, A Feast of Carols, 4 and 7:30 p.m., Dec. 11, St. Paul’s Episcopal Church, Chestnut Hill. Tickets: $25-45. Information: mcchorus.org.

Singing City: Joy Abounds — Singing City at the Holidays, 3 p.m., Dec. 12 at Bryn Mawr Presbyterian Church. Tickets: $26. Information: singingcity.org.

Temple University Choirs: For information on the university’s seven choirs and their concerts, boyer.temple.edu/temple-university-choirs