Abstract: At about 3:00 p.m. on September 9, 1991, Employee #1, a mason, and Employee #2, an apprentice, and a laborer were constructing a masonry chimney for a townhouse. They were working from a tubular welded scaffold six frames high (36 ft) by one frame wide with six platforms. Each platform was stacked with approximately 300 bricks each. The Employees were laying face brick and were moving the side bracket platform, which had been at a height of about 9 ft. The employees had removed the platform to raise it about 3 ft to the next level when they noticed that there was not enough room for the platform--the planks were touching the brick. To make room for the platform, they needed to move the scaffold out from the chimney by lowering the two screw jacks on the outside (back) of the scaffold. The laborer was lowering the right side and Employee #2 was lowering the left side. Employee #1 was on the 2nd floor platform of the scaffold, directing the lowering of the jacks. The laborer had completed lowering the right side and left the scaffold to mix mortar. Employee #2 was still lowering the left side when he noticed material falling and realized the scaffold was collapsing. He was struck by a bucket and knocked down to a sitting position and then buried to his waist by falling material. Employee #2 sustained lacerations to his head and back. He was transported to Frederick Memorial Hospital, treated and released. Employee #1 fell from the scaffold next to the basement wall and was buried by falling material. He sustained lacerations requiring stitches to his head and arm, and several broken ribs. He was transported to Suburban Hospital, where he was hospitalized for several days. The accident appears to have been caused by the lowering of the outside jacks, which brought the scaffold out of plumb. The scaffold was fully stacked with brick and there was also some brick on lower platforms. The scaffold platforms were overloaded with material. The employees were not wearing protective helmets and safe access to the scaffold was not provided.