SWAMPSCOTT – The Occupational Health & Safety Administration is in the process of investigating a construction accident that occurred Tuesday morning on Buena Vista Street.Three men were roofing a new house at 41 Buena Vista St. when a bracket supporting their scaffolding broke through a wall at approximately 9:20 a.m.Police Chief Ronald Madigan said improperly attached scaffolding appears to be the cause of the accident.?Essentially it looked like one end was attached to particleboard,” he said. “The bracket that supported the staging pushed through the particleboard.”OSHA Spokesman Ted Fitzgerald said he cannot release information on workers, but the company involved was A.F. Construction out of Swampscott.According Madigan, Kevin Kuppim, 40, of Beverly; John Goslin, 32, of Gloucester; and Tim Shennett, 25, of Exeter, N.H. were all injured in the accident, but are expected to recover.Madigan said A.F. Construction was working as a sub-contractor to A.C. Castle Roofing, which is located in Peabody.A spokesman for A.C. Castle Roofing said he heard the framers, who are not affiliated with his company, installed the brackets themselves.Swampscott Building Inspector Alan Hezekiah said the wall construction where the scaffolding collapsed appears to be made of standard 7/16-inch composite wood board.?The entire sheathing of the building was made of composite board,” he said. “A collapse occurs when there is too much weight on the scaffolding for the side of the home to support.”Contact information was unavailable for A.F. Construction but according to Hezekiah the building permit for the project was pulled by Mike Faia, who is listed as the homeowner on the building permits.Fitzgerald said the investigation involves looking at any equipment on the job site, any safety standards that apply and whether safety standards were adhered to. According to Fitzgerald, an OSHA investigation must be completed within six months.