Since we have commented on this provacative and serious issue before, I thought it important to brief our readers on the details of the announcement.
It's important to understand this announcement does not confirm or indicate these electrical breakers are now safe to use.
The CPSC has announced it is closing it's investigation without making a determination as to the safety of FPE circuit breakers or the accuracy of the manufacturer's position on the matter. The decision is being announced due to insufficient data to accept or refute claims made, and lack of funds to pursue. The Commission is still advising consumers to take the appropriate safety precautions listed at the end of the document being released.
In brief, the issues with FPE Stab-lok breakers began when it was discovered calibration tests during the design phase may have been inaccurately reported and data provided to Underwriters Laboratories was falsified. There were numerous field reports that Stab-lok breakers were not tripping appropriately as expected, eventually leading some experts in the industry to labeling the breaker design as a 'latent fire hazard'.
I encourage each one reading this blog who has an interest in or potentially has contact with these devices to read the official statement and the prefatory note from the CPSC staff.
Additional reading is available at this link, which reveals extensive research and comments specific to this topic from Dr. Jesse Aronstein, Consulting Engineer who may know as much about this electrical issue as anyone.