A steak was cooked medium after 2 1/2 hours on a postal truck's dashboard, an Arizona lawmaker says.

The postal worker cooked the steak to show how hot the trucks can get in the summer, said the lawmaker, state Rep. Shawnna Bolick.

Bolick, a Republican who represents Arizona's 20th Legislative District, is urging the Postal Service's workers' union to take action.

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It's hot in Phoenix — so hot you can cook steak on the dashboard of a mail truck, apparently.

That's what one postal worker did to call attention to hazardous conditions, and his call is being echoed by an Arizona lawmaker.

"It has come to my attention that quite a few USPS employees over the past few weeks in the Phoenix area have been sent to the emergency room to deal with heat stroke and heat exhaustion," Rep. Shawnna Bolick, a Republican who represents Arizona's 20th Legislative District, said in the letter, sent last Wednesday to the American Postal Workers Union leadership and Postal Service executives.

"In a few cases, these postal carriers have been hospitalized for several days and at least one was disoriented in their mail truck," she said.

She said that over 2 1/2 hours, one letter carrier managed to cook a steak to 142 degrees — medium — on the dashboard of his delivery truck, which has had an average temperature of 128 degrees. (The 142-degree sear falls just short of the 145 degrees the Food and Drug Administration says is the safe minimum internal temperature for steaks.)

Read more: July was likely the hottest month ever, and experts say it has 're-written climate history'

It's not clear whether the postal worker ate the steak after doing a brief photoshoot to show its doneness. The photos were included in Bolick's letter.

In July, a record-breaking heat wave swept the United States and much of the world. Heat is the leading cause of weather-related deaths in the US, killing an average of about 130 people a year.

"I would like to know what your organization is doing to improve your employee's working conditions," Bolick's letter concluded. "I implore you to review any safety or incident reports that have been filed and hold necessary hearings to help improve the working conditions of your members because right now they are inhumane."