Apple today said that auditors from a labor rights group have begun inspections at Chinese factories that manufacture its iPad and iPhone.
The audits were the first since Apple joined the Fair Labor Association (FLA) last month after acknowledging that aluminum dust was responsible for explosions at two of its Chinese suppliers last year that resulted in four deaths and injuries to another 77 workers.
Apple was the first technology company to join the FLA as a participating member, the organization said in mid-January.
The FLA investigations began Monday at Foxconn facilities in Shenzhen, China, a major center of electronics assembly in the southern part of the country that abuts Hong Kong.
"We believe that workers everywhere have the right to a safe and fair work environment, which is why we've asked the FLA to independently assess the performance of our largest suppliers," said Tim Cook, Apple's CEO, in a statement .
One of the two explosions occurred at a Foxconn plant in Chengdu, China, last May. The other took place at a Shanghai factory run by RiTeng Computer Accessory, a subsidiary of Pegatron , another Apple supplier, two months ago.
Chengdu is in southwest China.
In Apple's January 2012 report on worker safety, labor rights and environmental impact, Apple said it had audited all its suppliers that handled aluminum dust -- produced during milling and polishing of the iPad 2 and MacBook laptop cases -- and had required them to put new safety measures into place.
The one supplier that had not would remain shuttered until it met the new guidelines, Apple said in the report.
According to Apple, the FLA team will interview thousands of workers, inspect manufacturing facilities and worker living quarters, and review suppliers' documentation.
The results of the first round of audits will be published on the FLA website next month, Apple promised, and additional investigations will target other major suppliers, including Pegatron and Quanta.
The latter, like Foxconn and Pegatron, is a Taiwanese company with extensive operations in the People's Republic of China. Quanta bills itself as the world's largest maker of notebooks, and builds Apple's MacBook laptops.
Apple has been criticized for the working conditions at some of its partners' plants, prompting online petitions calling for changes, including one at Change.org that has collected more than 200,000 signatures.