Sonny Perdue picked as designated survivor for the State of the Union One official is asked to hang back from big events in case of an emergency.

 -- Sonny Perdue is taking one for the team.

The Agriculture Secretary was announced as this year's designated survivor, meaning that he was tapped to skip the State of the Union address and be secured at an undisclosed location instead, according to the White House pool report.

He later tweeted "I'm not in the House chamber tonight, but I'm watching and looking forward to a common sense #SOTU from @POTUS that is optimistic and unifying."

The designated survivor is typically a Cabinet-level official who is chosen to skip certain high-profile events — generally limited to State of the Union addresses and inaugurations — so that he or she may assume power if a disaster were to occur while the majority of the government is gathered at the event.

The annual State of the Union address is included because the president, both houses of Congress, members of the Cabinet and Supreme Court justices are often in attendance. Shortly before the president's speech, the designated survivor is whisked out of the nation's capital, accompanied by presidential-level security and a military aide carrying the "football," a briefcase that houses the nuclear launch codes.

Perdue, 71, served as governor of Georgia from 2003 to 2011 and worked on Trump's agricultural advisory committee during his presidential campaign. He is also a veterinarian and served as a captain in the United States Air Force.

The last designated survivor before Perdue was a veteran of sorts. Jeh Johnson, who served as the Secretary of Homeland Security, was named the designated survivor for President Obama's last State of the Union in 2016 and during President Donald Trump's inauguration in January 2017.

He told ABC News that he "can't go into the details" of how he spent that time, but noted that the two different types of events make the designated survivor's experience "two fundamentally different exercises."

For the inauguration, Johnson noted how the designated survivor is "serving two administrations," and in his case, he had to withdraw his resignation and make it contingent on the confirmation of his successor.

It took several hours for his successor to be formally appointed, however, so "I was actually Donald Trump's first Cabinet member for seven-and-a-half hours.... that was the entirety of his Cabinet for that time."

"I went from being secretary of homeland security with Secret Service protection and the designated survivor, fourth in line to the presidency, to being a private citizen," Johnson told ABC News.

ABC News' Jordyn Phelps contributed to this report.