Before Ali Stagnitta, 26, an entertainment reporter who lives in Greenwich Village, could attend a weekend retreat in the Catskills last month organized by Soho House, a private club, she had to check off a few things.

A fashionable face mask for group meditation sessions? Check. Warm jacket and gloves for nights around the campfire? Check. A 1,600-word waiver that absolves Soho House of any liability in case she became infected with the coronavirus during her two-day stay in a tiny cabin nestled on 105 acres? Signed and emailed.

“It’s the same thing as when they take your temperature,” said Ms. Stagnitta. Besides, she noted, each party had its own cabin, in which they prepared and ate their own meals.

Also, group activities including hikes and a nature photography class were outside and socially distanced. And masks were required.

While social gatherings are curtailed in many states, many people are still trying to gather.

Coronavirus waivers that must be returned with your R.S.V.P. are becoming a new norm for social events this season, including holiday parties, birthdays, weddings, proms, large-scale celebrations and even family reunions.

Hosts say that they don’t want to be held legally responsible in case one of their guests gets infected at their event, while larger outfits like Soho House say the waivers are just an extension of existing policies.

“I don’t want to take that chance,” said Andrea Adelstein, who runs NYLux Events, a company in Manhattan that stages weddings, bar and bat mitzvahs, and corporate parties. In addition to securing the caterer and florist, her company now sends out coronavirus waivers for guests to sign when they arrive at the event.

Ms. Adelstein has also signed her fair share of waivers. “I haven’t kept track of how many I’ve signed,” she said. “I understand why they are asking me to sign it. I know I have a high level of personal responsibility.”

Guests are usually happy to sign, often because they don’t believe they will get infected.

“If I have to sign a waiver, I have to sign a waiver,” said Karan Eschweiler, 54, a retired public school administrator from St. Charles, Mo., who signed a waiver before attending a 100th birthday celebration last month for Stan Musial, the storied St. Louis Cardinals baseball player, at Busch Stadium. “What I do for fun is go to the Cardinals games. So I kind of felt like, this is my chance to get into the stadium and do something Cardinal related.”

Scheduled for late November, it was supposed to be an outdoor parade with music and cupcakes, but was turned into a drive-by party when Covid-19 cases rose in the region.

And it’s not only guests who are being asked to sign. Employees who work at social events are being asked to waive their rights to sue, too.

When Joe Snell, 46, who runs Central Arkansas Entertainment, a D.J. booking company in Little Rock, Ark., was asked to sign a waiver for a September wedding, he didn’t hesitate. “I didn’t fight it because I knew we had to do it,” he said, adding that his bookings dropped to 600 from 2,600 this year. “In our industry if you want to work, you need to be out there at these events.”

Are They Enforceable?

Coronavirus waivers, which surfaced when lockdowns were lifted in late spring and have grown in popularity since, vary widely in scope and length. While many were drafted by individual lawyers, legal templates can also be found online, on sites like Jot Form and Paperform.

Most require that the person signing the waiver acknowledge the risks of attending a social gathering, agree to comply with government health and safety protocols, inform the host if the person tests positive before the event and, perhaps most pertinent, waive the right to sue if the person becomes infected at the event.

“In exchange for admittance into the event and use of the facility,” reads one waiver offered by a catering company in Philadelphia, “I therefore accept the risk of attending this event.” The waiver promises to “relieve” the organizers, host, venue owners and event management company “from any loss, damage, claim and/or demand on account of injury, sickness or death arising from attending the event.”

But it’s not clear whether the waivers offer any legal protection or are enforceable in court. For starters, it’s not easy to prove where someone got infected, so a waiver may not be necessary to protect a host from being sued.

And even if guests could trace their infection to a specific gathering, the waiver may not hold up in court, said Seta Accaoui, a lawyer with CMBG3, a corporate law firm in Boston who specializes in liability law.

“It’s not going to shield you from total liability, it’s not a slam-dunk defense,” she said. “Courts are going to look into the circumstances and the situation you are presenting. They will want to know if the hosts were mindful of the risks, and what they were doing to implement safety procedures.”

Nonetheless, citing the proverbial “abundance of caution” that has become a pandemic cliché, Ms. Accaoui encourages all of her clients —- including spas, youth sports groups, restaurants, golf tournament and schools — to use waivers.

Still, the waivers are so new that none of the lawyers interviewed for this article were aware of any cases that invoked them. “The only way to know whether or not the given waiver is going to be found effective is for someone to file a lawsuit and have it go all the way through the legal system and have a judge or jury make a determination,” said Patrick Schoenburg, a lawyer in Fresno, Calif., who specializes in litigation arising from infectious diseases.

The legal issues become murkier when the event in question violates local social-distancing rules. “You can’t ask someone to waive their rights if they attend a party that is in violation of a city or state’s restrictions,” Mr. Schoenburg said.

He also warns that waivers could backfire, should a case ever reach a trial. “What is a jury going to think about a person who held a 100-person wedding and,was so aware that this was a dangerous practice, that they asked everyone to sign a stupid contract they found on the internet?” he said.

‘They All Have Waivers’

For those reasons, Tom Ryan, a personal injury trial lawyer in Chandler, Ariz., has been warning parents in his neighborhood not to sign waivers for their children’s proms, homecoming dances and soccer tournaments. The waivers may offer some protection for the hosts, he said, but offer nothing for the child and family.

Mr. Ryan said he knew of many parties and events happening, and “they all have waivers. What it is saying is, ‘I can be as negligent as I want, harm you as much as I want to, and you can’t sue me.’”

That was the realization that Kiersten Clark, 24, a merchandise coordinator for West Elm in Brooklyn, reached when she was invited to her cousin’s 150-person wedding in Central Florida in November. As she debated whether to go, she learned that neither masks nor coronavirus tests would be required. Then she heard about the waiver.

“My first and continuous reaction is anger,” Ms. Clark said. “They knew the chances of someone getting the virus, especially with a lack of masks, was high, and that their selfishness in continuing to have the wedding should have consequences. Hearing about the waiver sealed the deal for my decision not to go.”

She has since learned that two relatives tested positive for the coronavirus after attending the wedding.

The wisdom of virus waivers may be dubious, but when faced with the choice of signing a pro forma waiver, or spending another day stuck at home on endless Zoom calls, many people will opt to sign.

“I took my 18-month-old daughter to a farm the other day, and the Covid-19 waiver form was four pages,” Ms. Accaoui, the Boston lawyer, said. “In order for me to get my picture of my daughter petting that baby goat, I had to sign that document. And so I did.”