When manners are your family business, you are extra careful where you use your cellphone.

Daniel Post Senning, 41, the fifth generation to write “Emily Post’s Etiquette,” now in its 19th edition, does not engage with his iPhone at the dinner table.

But many of us have experienced lovely gatherings jarred by the beeps and buzzing of nearby phones. The alerts are irritating enough, but even more so when texts, calls or FaceTime invitations are answered and the guest is no longer participating in the meal. “We are programmed to respond to these devices,” says Senning, who is co-president of the Emily Post Institute in Burlington, Vt. “It’s not that you realize you’re being rude. It’s just the habitual use that triggers you to respond immediately.”

It’s not hard to slide down the slippery slope of phone zone-out. We’ve all seen it happen. Someone went to a lot of trouble cooking a lovely meal and setting a nice table to bring friends together for a relaxing evening. “There is a lull in the conversation and someone checks the score of a game or a text from a friends group and all of a sudden they are locked into their phone and aren’t participating socially,” Senning says. “But staying present is very important, and it can pay real dividends in getting to know people and avoiding unintentional rudeness.”

What would Senning do if, during a dinner at his house, a friend were spending too much time looking at their phone? Senning says he would not call out the person at the table. “I would probably take note of it and say something before we all sit down together the next time,” Senning says. “I’d say something like, ‘I heard your phone going off during dinner, it would be great if you could silence it while we’re at the table.’ ”

Because so many of us eat on the go or while watching Netflix, actually sitting down and sharing a meal with friends is a cherished and powerful ritual that occurs far less frequently these days. Yet, Senning says, many of are unsure of how to deal with phones during these times.

Cellphone and communication issues, along with table manners and weddings, are the topics Senning and his colleagues are asked most for guidance about. I asked Senning for tips on phone use at gatherings. The responses have been edited for length and clarity.

Q: Is it okay to put your phone on the table at a dinner party?

A: No. There is no place at a place setting for your phone. The dinner table is the most important social ritual that we engage in with others. We should concentrate on that. Phones should be off.

Q: Are rules still evolving?

A: Yes, but I say that cautiously. They shook out years ago. It didn’t take long for people to start thinking that they didn’t want their phone to be an imposition, and you needed to shut it off at a theater or restaurant. And also where there is a captive audience, such as in an elevator or at a dinner table. If people can’t get up and leave, you don’t subject someone to half a conversation.

Q: In Washington, you might be hosting a journalist on deadline who is expecting a call from an editor. How should this guest handle this?

A: If it’s important enough that you would be stepping away from the dinner, let your host know ahead of time. Say, ‘I’m expecting a call from my editor so you might see me checking my phone occasionally. But when I need to make a call I will go into another room.’ This shows consideration and respect, self-awareness, and awareness of others.

Q: What about smartwatches?

A: It’s less obtrusive to look at a watch, yes. But back in the day, there were these manners about being careful about obviously checking your watch. This was considered rude, like you were getting bored. Sure, if you see that email and an alert and it’s not distracting to other people. If it’s there on your wrist, okay. But don’t start interacting with it.

Q: What about offering guests a five-minute tech break before dessert?

A: It’s better than the alternative, which is everyone being on their phones all night. If you consider that good hosting for your guests, and it makes people feel comfortable, then do it.

Q: What do you consider "turning off" your phone if you don't want to just power it off?

A: To silence your iPhone, you should turn the ringer off using the button on the side and turn off the vibrate function in settings, or you should turn on the “Do Not Disturb” mode.

Q: What if you want to Google a fun fact at dinner?

A: Oh, like what was John Wayne’s second movie? I’m of two thoughts — I love challenging people — the challenge of not knowing can be part of a good conversation. There might be a benefit in keeping the conversation going. However, I don’t feel that it’s rude to use a phone in the service of a shared activity. So I give an exception of the rule that asks you to stay off your phone at the table.

Q: Would your advice be the same for millennials and boomers?

A: My advice would not change: Manners are situational. There are core principles for good etiquette that are consideration, respect and honesty. These apply for host and guests. The idea that you would get on your phone in the middle of a conversation, whether you are 24 or 54, is annoying.

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