President Obama’s nominee to run the Environmental Protection Agency assured Republicans on Thursday that she does not use personal email accounts to conduct official business.

Republicans have slammed the use of personal email accounts by other EPA officials, arguing they are being used to shield decision making from public view.

But Gina McCarthy, who now serves as EPA’s air quality chief, said she’s always used government systems for her work.

“I do not conduct business through personal email,” McCarthy told Sen. David Vitter (R-La.), the top Republican on the Environment and Public Works Committee who is vetting her nomination.

McCarthy said she has used a personal account only for convenience in moving documents, and in a way that ensures the communication is available under public records laws.