Yale challenged the findings, saying the machinery did meet national safety standards.
Dufault, a physics and astronomy major from Scituate, Mass., who was close to graduating, was alone in the lab when her hair was pulled into a spinning lathe.
The lathe, built in 1962, lacked an emergency stop button that could shut off power and was missing physical guards to protect the operator, OSHA wrote in the letter.
The OSHA letter said rules for using the equipment, including warnings, were not posted. Yale also should ensure students do not work alone, establish specific hours of operation, and implement a formal training program.
Surveys of protective equipment were not completed and documented, and safety inspections did not address machine safeguarding, the letter said.
Asked whether OSHA would have fined Yale if it had jurisdiction, Robert Kowalski, the agency’s area director, said, “That’s a good possibility.’’
Yale says it provided extensive machine tool training and personal protective equipment and students were repeatedly told not to use machinery without someone else present.
“Unfortunately, OSHA’s assessment contains a number of significant inaccuracies,’’ Yale said in a statement.
School officials said after the accident that the university was stepping up its safety training and would limit access by undergraduate students to hours when monitors were present.
Yale has said Dufault completed a safety course that included instructions to tie back long hair.
