NASA-LLIS-5496
Lessons Learned - Vehicle Assembly Building (VAB) Fall Protection Barrier Chain Guard Rail Failure with “S” Hooks
| Organization: | NASA |
| Publication Date: | 2 June 2011 |
| Status: | active |
| Page Count: | 3 |
scope:
Description of Driving Event:
A contractor at KSC was on a project to refurbish the outside of the VAB. The refurbishment effort includes horizontal and vertical doors in High Bays 2 and 4, the South Transfer Aisle Door, translucent panels, and upgrades to exterior siding. The contractor hired a sub to perform surface preparation and painting. On May 19, 2008, The subcontractor began their work shift and held a morning tag-up meeting with employees. Tasks were assigned and the subsequently injured painter (P1) and a co-worker (P2) were dispatched to the 41st floor of VAB High Bay 4 to prepare vertical door canopy steel beams for painting.
The painters arrived at level 41 at approximately 7:30 a.m. and performed tool and equipment inspections. They then donned and checked appropriate Personal Protective Equipment (PPE) including long-sleeved shirts, goggles, hard hats with face shields, earplugs, respirators, and Personal Fall Arrest Systems (PFAS), consisting of a body harness and lanyard. They descended a ladder to their work area, a catwalk platform, level 41A. Level 41A is protected on the south side by a guardrail and on the north side by a wall.
Once on level 41A, the painters used their training and experience to determine where on the platform they needed to have their Personal Fall Arrest Systems (PFAS) anchored in order to arrest a potential fall. P1 began needle-gunning a vertical member in the center of the platform and did not hook up (anchor) because protection was provided by the wall and guardrails. P2 hooked up and began needle-gunning near an unprotected edge at the east end of the platform.
P1 finished the vertical member and proceeded to the west end of the platform. At this location there is a ladder access opening in the guardrail. This access is protected by chain barriers. P1 observed that the top chain was connected and concluded that no hook-up was required in this location. P1 began needle-gunning an overhead beam facing away from the ladder opening chains. Needle-gunning is a two-handed operation. The workspace between the "S" hook chain guard rail barrier and the structure being prepped is 13 inches. P1's buttocks periodically began to make contact with the top "S" hook chain guard rail barrier while needle gunning. P1 became comfortable with touching and leaning on the chain barrier while performing the task.
At approximately 8:10 a.m., P1 leaned against the chain S-hook once more, and it disengaged from its eyebolt. P1 fell through the ladder opening approximately 12 feet to another service platform, level 41B, an unguarded platform nearly 500 feet above the VAB floor. The top chain remained attached at the latch end. P2 heard a "boom, boom, boom" noise and looked for P1. P2 found P1 lying on level 41B. P2 yelled to P1; P1 was nonresponsive and appeared unconscious. P2 went to level 41 and informed a colleague that P1 had fallen and needed help.
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