Apple has admitted that more than a third of its suppliers are failing to comply with its rules on working hours - and that the situation's been getting worse.
In its annual report on working conditions, it says that workers at 38 percent of its suppliers are working more than 60 hours per week, up from 32 perccent in 2010. More than half the workers at 93 plants were working over this limit during a 12-week audit period.
Involuntary labor was being used at 17 factories, and child labor at five. Pay was being docked for disciplinary reasons at 67 facilities, while 42 were delaying payment and 108 failing to pay proper overtime.
The company's also admitted that explosions at two plants were caused by combustible aluminum dust in the atmosphere. It says it's introducing new rules aimed at improving ventilation and making fire extinguishers more readily available.
Following relentless criticism of Apple's human rights record, particularly at supplier Foxconn's Chinese plants, the company says it's now signed up to the Fair Labor Association - the first technology company to do so.
"We found that Apple takes supplier responsibility seriously and we look forward to their participation in the Fair Labor Association," says Auret van Heerden, FLA's President and CEO.
"We welcome Apple's commitment to greater transparency and independent oversight, and we hope its participation will set a new standard for the electronics industry."
Apple's also, for the first time, listed a more-or-less complete list of its partner companies.
They include Kunshan Changyun Electronic Industry and Catcher Technology, both listed by pressure group China Labor Watch as having a human rights record worse than the Chinese average - as well as numerous other companies too small for CLW to investigate.
Still, it's perhaps a little churlish to complain (Chinese workers might not agree), given that Apple is creating greater transparency over its supply chain than ever before.
"Last year, we performed more than 200 audits at our supplier's facilities around the world," says Jeff Williams, Apple's senior vice president of operations.
"With the benefit of the FLA's experience and expertise, we will continue to drive improvements for workers and provide even greater transparency into our supply chain."
The full report's available here.