WATCH: Transportation Sec. Buttigieg holds briefing on impact of possible government shutdown

The nation’s air-travel system is expected to operate relatively normally during a shutdown. Air traffic controllers and TSA screeners are deemed essential workers — however, those people won’t be paid until the shutdown ends, and TSA lines could grow longer if enough screeners stay home.

Watch the event in the player above.

Transportation Secretary Pete Buttigieg said Wednesday that air travel will remain safe in a shutdown, but that the training of new air traffic controllers will stop and 1,000 trainees will be furloughed.

Long before this week’s deadline, airlines were already been complaining that a shortage of air traffic controllers has been causing flight delays and cancellations. The Federal Aviation Administration said in August it hired 1,500 new controllers in the past year and asked Congress for money to hire another 1,800 in the new fiscal year.

WATCH LIVE: Senate convenes as House Republicans continue budget battle and shutdown deadline nears

The processing of passports and visas will continue in a shutdown “as the situation permits,” according to guidance that the State Department gave employees last week. The department said consulates in the U.S. and abroad will say open “as long as there are sufficient fees to support operations,” but passport work could stop if the building where the work is done gets shuttered.

The time it takes to get a passport or visa already is much longer than before the pandemic. Most Customs and Border Protection agents are also considered essential and would be expected to work at airports and border crossings.

The Senate passed a bipartisan continuing resolution Tuesday evening to continue funding the government through November, but the House of Representatives remains steadfastly divided, with House Speaker Kevin McCarthy working to wrangle the resistant far-right of his party.

On Monday, Buttigieg announced more than $1.4 billion in funding for projects to improve railway safety and increase capacity. About $1 billion of that funding came from the 2021 infrastructure law, which authorized up to $108 billion for public transportation.