The recent revelation that a senior official at the National Weather Service helped write his own job description for a cushy post-retirement consulting position — then was back at work the day after he left — has drawn scrutiny not just because of the eye-popping details.

The Donald Jiron case, investigated by former Commerce Department Inspector General Todd Zinser, also has raised a key question: How often are revolving-door rules broken in government? Sen. John Thune (R-S.D.), chairman of the Commerce, Science and Transportation Committee, is asking the National Oceanic and Atmospheric Administration pointed questions about the practice of civil servants returning as contractors to pretty much the same job they had in government.

In a letter last week to NOAA Administrator Kathryn Sullivan, Thune noted that the misconduct the watchdog described in a report this month  may be “indicative of a routine and troubling practice at NOAA of hiring former employees as contractors for purposes of carrying out similar duties to those they performed prior to leaving federal office.”

“The fact that senior agency officials approved this unseemly arrangement, which clearly warranted closer scrutiny, appears to be indicative of a potential agency-wide problem,” Thune wrote on June 11. “In order to maintain the integrity of the agency, NOAA officials must avoid conflicts of interest and adhere to and enforce federal hiring and contracting rules.”

Jiron, the Weather Service’s deputy chief financial officer, had demanded that he be paid a $50,000 housing allowance for a home near the agency’s headquarters in downtown Silver Spring, Md., according to investigators. This was a clear violation of government rules for contractors and one of numerous improprieties in a revolving-door deal sealed with full knowledge of senior agency leaders.

In the course of questioning by investigators, a high-ranking Weather Service official wondered aloud, “Why do we have all these people that retire and then we go and hire them to come back?” The contracting official who helped arrange the deal told investigators that similar arrangements “happen all the time” at NOAA  — but that the contracting staff did not “question or at least more closely scrutinize this arrangement,” the report said.

Jiron’s attorney, Matthew Kaiser, has noted that his client’s supervisors approved his work arrangement and said because of that Jiron did nothing wrong. Were similar deals part of NOAA’s culture when Jiron returned as a contractor with a $43,200 salary increase over his GS-15 pay? He was fired in 2012 after working 21 months doing a very similar job to the one he held on staff.

Thune is trying to determine whether Jiron’s procurement of his own post-retirement job appears to be common throughout NOAA, the Weather Service’s parent agency.

The government has strict rules for senior officials who want to return to their agency as contractors: It’s a no-no, for a time. You can’t get near the agency for business for two years if you’re a political appointee; the grace period for civil servants is a year.

And if you were involved in awarding a particular contract while in the government, you’re banned for life from working on it once you leave government.

“It brings into question the integrity of the whole organization,” Jeffrey Neal, a longtime federal personnel manger, said of revolving-door violations.

“You’re clearly told what the rules are,” said Neal, who retired in 2011 as human capital chief for the Department of Homeland Security and is now a vice president at ICF International.

“The appearances when they’re broken are terrible.”

Thune has asked Sullivan for data on how contractors employed by NOAA get hired, including how many of them previously held staff positions, the average salaries of contractors over three years compared to civil servants with the same responsibilities, and whether the agency has any protections to ensure that current federal employees “are not involved in drafting job descriptions for contract positions they intend or hope to fill themselves.”

A NOAA official said the agency put new protections in place in 2012 against conflicts of interest in filling contracting positions, although he did not offer details. The official, who spoke on the condition of anonymity because NOAA has not responded to Thune’s letter, said the two supervisors who approved Jiron’s arrangement, both senior officials, were “removed” in 2012, but declined to say whether they were fired or pressured to retire.