less than 50 hours weekly. Producing the chart was a simple response to the problem of excessive overtime, but it seemed to work, according to Apple. The Cupertino based tech giant has a Supplier Code of Conduct that says that employees must be limited to 60 hour work weeks except in "unusual circumstances" (like when demand for a certain device is high?), and all overtime must be voluntary.
Besides keeping workers toiling for less than 60 hours a week, Apple says it has been stringent with suppliers to prevent underage workers from entering the factories. In its latest report, Apple says, "In 2012, we found no cases of underage labor at any of our final assembly suppliers." In one case, Apple found out that a specific labor agency was providing underage workers to a factory that Apple stopped doing business with due to its underage employees. Apple reported this to the provincial government which suspended the agency's license and fined it.
source: Apple via TUAW