Interesting Field Experiance

Earlier this week I went on a site visit as part of a design meeting. The the facility has an underground vault filled with mechanical and electrical equipment. A visual inspection of this equipment is necessary so a coworker (an Electrical Engineer) and myself (a Mechanical Engineer) went inside the vault.

Breaker box that hit me

After looking around at some of the equipment I heard an odd noise coming from an electrical panel on the opposite wall about 10 feet away. Quickly looking up, I saw sparks emanating from it followed by a loud boom. At that instant the panel flew open and a breaker flew across the room and hit me in the chest. Unhurt, but very surprised, I noticed the box bounce off me and land several feet away. Turning to my coworker I said, "You need to fix that in your design."
When we left the vault I noticed a black mark on my shirt, but it simply wiped off. I suppose the breaker box was simply dirty, so unfortunately I do not have a singe mark to show off.

Control Panel