Abstract: On September 22, 1993, at approximately 10:45 a.m., employees of John R. Mulford & Son, Inc., were repairing the roof on a two story wood dwelling in Millington, MD. Employees #1 and #2 were installing shingles from an unguarded 14 inch Werner Task Master scaffold plank 18 feet high on a pump jack scaffold 30 feet in length. A third employee was climbing an extension ladder used to gain access to the left front of the scaffold. The right pole, 24 feet in height, approximately 4 inches in width, and consisting of two 16 foot 2 by 4s and two 8 foot 2 by 4s inches, failed 7 feet 10 inches from the bottom. As a result, the right side of the pump jack scaffold collapsed when the bracing at the top of the pole pulled out of the eave of the roof where it was attached with 16 penny nails. Employees #1 and #2 fell 18 feet to the ground while the third employee's ladder came to rest against the eave. Employee #1 received bruises and lacerations, and was treated and released. Employee #2 complained of back pain and was admitted for observation at Kent's Queen Ann Hospital. No one at the site was familiar with pump jack installation or inspection requirements.