Katherine Andrea Lemos

Katherine Andrea Lemos is an American safety professional and the former chairperson and CEO of the U.S. Chemical Safety and Hazard Investigation Board (CSB).

Early life Katherine Lemos was born to John Curtis and Laura Curtis. She also worked as a postdoctoral researcher at University of Iowa Operator Performance Laboratory and as a NASA Faculty Fellow at Langley Research Center.

Lemos is a pilot and certified flight instructor. She had previously worked as a technical leader and program manager for aviation safety at the Federal Aviation Administration and as an accident investigator and later Special Assistant to Vice Chairman of the Board of the National Transportation Safety Board. She had also held academic positions at University of Maryland and Instituto Tecnológico de Aeronáutica.

Lemos has specialized in system safety, accident investigation, and human factors. On July 22, she was nominated by President Trump to serve concurrent five-year appointments as chairperson and CEO of CSB. At the time, the CSB's five-seat board had only three members, one of whom would leave in December 2019.

A hearing on her nomination was held by the United States Senate Committee on Environment and Public Works in September 2019. Senator John Barrasso said "it was critical the Senate confirm Dr. Lemos to provide a working quorum to the board"; at the time of Lemos's confirmation, the CSB board had only one member, Kristen Kulinowski, She began her tenure on April 23, 2020. At this time, CSB had ten unfilled investigator positions. Thereafter, Lemos declared that she could operate as a "quorum of one", citing a legal opinion from the CSB general counsel allowing her to unilaterally run the CSB. A July 2020 Environmental Protection Agency Office of Inspector General report concluded that it remained an open question whether a single CSB board member may constitute a quorum, as doing so would impair the segregation of duties mandated by the Government Accountability Office.

In May 2021, Public Employees for Environmental Responsibility criticized Lemos for accruing $33,000 in travel expenses and $20,000 in office renovations, and for hiring a senior advisor from Northrop Grumman for an undisclosed salary. She said that she intended to expand the staff of CSB to 61 people by September 2023.

Lemos submitted her letter of resignation to the White House in June 2022, citing lost confidence in the board's focus on the agency's mission. Her resignation became effective on July 22, 2022.

In June 2023, the EPA Inspector General released a report stating that Lemos violated federal regulations for her use of board funds for travel, office refurbishment, and media training, but did not violate restrictions placed by a continuing resolution and did not violate regulations for the hiring of senior aides. Senator Chuck Grassley wrote a letter to Lemos requesting that she repay the money indicated as improperly spent in the report.