An undercover investigation by China Labor Watch at the Suqian plant last month found that fire exits were locked and that flammable aluminum-magnesium alloy dust and shavings filled the air and littered the floors of some workshops. Investigators also found that employees were forced to work as many as 100 hours of overtime a month and failed to receive the social insurance payments required under Chinese law, according to the report. It said the plant made aluminum covers for a coming iPad and parts for the iPhone 5. Workers at the plant, about 300 miles northwest of Shanghai, in Jiangsu Province, were also required by Catcher to sign forms saying they had completed safety training, even though they had received none, according to the report.
China remains Apple’s biggest single source of suppliers, and it is also where most of the company’s products are assembled. In a report on Monday, analysts at Bank of America’s Merrill Lynch unit in Hong Kong estimated that the expected release next week of the iPhone 6 could add around 1 percent a month to China’s export growth rate for the rest of this year.