The hand rail on a temporary stairway at a construction site failed, causing bodily injury to a workman. A typical temporary stair rail, constructed of angle iron and wire cable is shown in Photograph A.
Photograph A Temporary stair rail post as normally used at a construction site.
An overall view of the temporary stair rail post is shown in Photograph B. In Photograph B, it will be noted that the post attachment welds, denoted with white arrows, are the subject of this accident investigation.
Photograph B Temporary stair rail post. Arrows denote upper attachment weld.
A close-up view of the upper attachment weld, shown to the left in Photograph B, is shown in detail in Photograph C. It can be seen that rather than make a complete weld, the welder chose to weld over a long piece of welding rod. This is extremely poor welding practice. Arrows in Photograph C denote the improperly placed welding rod, which was then welded over.
Photograph C Upper attachment weld. Arrows denote location of weld.
A profile view, showing the very small amount of weld bead and the fact that the weld bead was intermittent, is shown in Photograph D.
Photograph D Showing weld bead and intermittent nature of weld deposit.
The lower post attachment weld is shown in Photograph E. This weld was so small that no areas of fracture could be found between the weld bead and the adjoining stair structure to which the post was supposed to be joined.
Photograph E Lower post attachment weld.
No metallurgical examination was conducted because the post attachment welds were so poorly welded that cutting for metallographic examination would have probably caused the attachment weld bead and welding rod to fall away, thus spoiling a perfect jury exhibit.
The cause of the subject construction site accident was inept and inadequate welding of the hand rail post to the stairway structure.