Abstract: Employee #1 and a coworker were installing grapples on a new D6H Caterpillar bulldozer, serial #6CK00401. They had placed portable stairs at each side of the rear of the bulldozer. Employee #1 was at the top of the stairs and, when he turned to descend, he struck his left knee against the corner of a section of flat steel that protruded from the back of the bulldozer. He sustained a small cut on his knee that was left untreated. The following Monday, the knee was sore and swollen. He went to work but started feeling sick. His doctor put him in the hospital, where he was admitted for two and a half days for treatment of an infected knee. The cut should have been treated immediately to prevent infection. The accident was not reported to the employer until Employee #1 went to the hospital. No safety violations were cited in connection with the accident. The employer operates a Caterpillar sales and repair facility.