Abstract: A method of repairing large coal fired boilers and the like using a special heat resistant suit which enables workmen to erect scaffolding in the boiler at about 1100.degree. F. and to enter the boiler at a temperature above 150.degree. F. to make the necessary repairs. Refrigerated air and air for breathing by the workmen are supplied from external sources through a special insulated hose having a breakaway connection with a fitting on one leg of the suit. The refrigerated air is distributed within the suit through apertured tubes and an apertured vest. Air for breathing is supplied to a face mask. A portable air tank automatically begins supplying the face mask when the hose is detached. A harness mounted safety reel and cable permits workers to drop from the scaffolding for fast escape in an emergency. A brake controls the rate of descent.