Teachers feel such stress at work  — from rising class sizes, mandates that come without money, and little respect from elected officials — that the leading American teachers union will ask the federal government Wednesday to formally study the health hazards of being a teacher.

A survey of more than 30,000 educators nationwide conducted by the American Federation of Teachers and the Badass Teachers Association found that more than 70 percent of teachers said they “often” find their work stressful, with another 24 percent responding “sometimes.”

The teachers chalked up the worst sources of their discontent to new initiatives that don’t come with proper training or professional development and to mandated curriculum and large class sizes, according to the survey.

The survey showed that 79 percent of teachers also feel disrespected by elected officials.

AFT President Randi Weingarten said the 80-question survey of a fraction of her 1.6 million members “wasn’t a scientific study” but hoped it’d be enough to spur the federal Department of Education and the Centers for Disease Control and Prevention’s National Institute for Occupational Safety and Health to formally study teachers’ workplace conditions.

“Right now in classrooms across the country, they are facing incredible challenges from stress, from standardized testing, from being thrown lots of requirements where they don’t have the time or the tools to actually implement, higher class sizes that have not been reduced since the recession and a lot of other things that have created a terrible situation,” Weingarten said Tuesday during a telephone press conference.

Illinois respondents accounted for about 7 percent of participants or about 2,000 teachers, counselors and social workers and other school staffers, according to the union.