Congress has moved to block an effort to weaken a federal board that oversees worker and public safety at nuclear facilities, adding language to an appropriations bill to prevent the agency from altering the board’s structure.

The bill also requires the Energy Department to answer questions from Congress about its recent attempts to limit the board’s access to information and change how the panel conducts its work.

The language protecting the board was introduced by New Mexico Sens. Martin Heinrich and Tom Udall, Democrats who have decried the Energy Department’s push to impose staff cuts and other changes on the Defense Nuclear Facilities Safety Board.

Established in 1988, the board reviews incidents and near-misses at the nation’s nuclear complexes, as well as providing safety recommendations and advice to the energy secretary. Three of the 14 nuclear facilities under the board’s jurisdiction — Los Alamos National Laboratory, Sandia National Laboratories and the Waste Isolation Pilot Plant — are in New Mexico.

Beyond an effort outlined by the Republican chair of the board to cut the agency’s staff, in mid-May the Energy Department published an order that, in the view of other members of the panel, substantially diminished its ability to perform its oversight role. The order, which was first reported on by the New Mexican and ProPublica, prevents board members from accessing sensitive information, imposes additional legal hurdles on staffers, and mandates that Energy Department officials speak “with one voice” in communicating with the board.

The Energy Department has said the May order is simply intended to clarify roles and responsibilities and to decrease costs, and is a necessary update to a manual relied on to guide the relationship between the department and the safety board since 2001. Officials said these actions were taken as part as President Donald Trump’s 2017 executive order to trim regulations.

But while the for-profit contractors that run the Energy Department’s nuclear sites were consulted on the changes, the board said they were given no formal input on them. Board members also have said the order would inhibit their ability to do key parts of their job, potentially violating the statute under which the board was created.

The board said it had no comment on the move by Congress to stall the changes.

In a joint statement, Heinrich and Udall said the provisions they had added to the appropriations bill demonstrated “that Congress shares the widespread concerns about DOE’s information sharing order,” adding that, in their view, the order should be halted.

“We will continue to work to make sure that the DNFSB has the resources, support, and independence necessary to carry out the complex and extremely serious work that the board does,” they said.

(The New Mexican and ProPublica asked the Energy Department for comment on the bill, but so far have not received a response.)

Congress’ steps to shield the board will become official if Trump signs the Energy and Water Appropriations Act of 2019, the bill to which Heinrich and Udall’s provisions were added.

Since the 1980s, the safety board has had largely unrestricted access to nuclear facilities around the country in order to make informed recommendations intended to prevent catastrophic nuclear accidents and harm to workers. The board’s reports are public, making it one of the rare windows into the Energy Department’s riskiest nuclear work.

But since the Energy Department’s May order came into effect, the board has been prevented from accessing some of the information its reports rely on, including a worker complaint at Los Alamos and other material from the facility.

The order could also prevent the safety board from overseeing the Waste Isolation Pilot Plant, where nuclear waste is stored in underground salt mines. A 2014 accident at the plant exposed workers to radiation and became one of the Department of Energy’s most expensive accidents in history.

Last month, at the first of three hearings held about the order, the board said the Energy Department failed to formally consult board members, workers or the public on the new restrictions. The board’s chairman also suggested the order could contradict the U.S. Atomic Energy Act, which grants the board wide latitude on information access.