Your colleagues probably do not want to overhear you talking on your cellphone about your cat's digestive problems.
Also, they generally don't like to see your gaze slip to your iPhone while you are supposed to be having an in-person conversation. Eyes up here, everyone!
Americans may love their smartphones—but they aren't necessarily so enamored with how their colleagues are using them in the workplace.
A new survey of 1,070 employed Americans, conducted by Harris Interactive on behalf of mobile business platform Jive Software, finds that almost everyone is annoyed by some type of bad phone etiquette at work.
The top offender, cited by 65 percent of those surveyed: Having loud or private conversations in public areas.
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Even in open floor plan offices, experts say this is something that can be easily avoided.
"Your mobile phone is mobile. Stand up, walk to somewhere that's a little bit more private to have those private conversations," said Sydney Sloan, Jive's social media expert.
It's not just your mobile phone conversations that are annoying your co-workers—it's also all those beeps and buzzes your phone itself is making. About 59 percent of those surveyed said they were annoyed by co-workers who fail to silence or turn off their mobile phones when it's appropriate.
If you are working in a cubicle farm, you should generally always have your phone on vibrate or silent mode, said Jodi R.R. Smith, owner of the etiquette consulting firm Mannersmith.
But even that may not be enough, she said, because the vibration your phone makes on your desk also can be grating to your co-workers.
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If you absolutely have to have your phone ringer on, make sure that the ring tone itself is work-appropriate.
"Some are more professional than others," she noted.