In 2011, Chinese environmental groups ranked Apple as the least responsive company among more than two dozen technology firms to concerns about working conditions at its factories. (Reuters)

Chinese factories where Apple devices are assembled are undergoing voluntary audits of their working conditions by an independent workers' rights watchdog that the company recently joined.

The Fair Labor Association began its first inspections Monday at a facility called Foxconn City in Shenzhen, China. That and other planned inspections are expected to include factories where 90 per cent of Apple devices undergo final assembly, Apple announced in a news release. However, the release did not mention factories that manufacture device components.

The FLA describes itself as a non-profit organization dedicated to ending sweatshop conditions in factories worldwide.

Apple has been heavily criticized in recent years for alleged health and safety problems and poor working conditions at Chinese factories that supply and assemble components of devices such as iPhones.

A spate of suicides at Foxconn Technology Group factories in 2010 and the illnesses of workers at Wintek Corp., in 2011, which were thought to be caused by exposure to toxic chemicals, both created bad publicity for Apple.

A 2011 report by Chinese environmental groups ranked Apple as the least responsive among more than two dozen technology companies to concerns about working conditions at its supplier factories.

Although Apple has conducted its own audits of its final assembly factories since 2006, this is the first time it has asked an independent group to inspect the facilities. The audits are voluntary, but Apple said its suppliers have "pledged full co-operation with the FLA, offering unrestricted access to their operations."

The audits will include interviews with employees about working and living conditions, including health and safety, working hours and wages, along with inspections of manufacturing and living areas and examination of employment-related documents.

The findings and recommendations from the first inspections will be posted online in early March.

"The inspections now underway are unprecedented in the electronics industry, both in scale and scope, and we appreciate the FLA agreeing to take the unusual step of identifying the factories in their reports," said Apple CEO Tim Cook in a statement.

The company noted that in January, it became the first technology company admitted to the FLA. Joining the association requires companies to commit to allowing unannounced independent audits and enforcing a special code of conduct in their supplier facilities. Other FLA "participating companies" include Nike, American Eagle Outfitters and Liz Claiborne.

Apple said it has conducted and posted results online of more than 500 factory audits it has conducted throughout its supply chain in the past five years.

Many of the companies that supply and assemble components for Apple devices, such as Foxconn, are also contracted by other technology companies, such as Microsoft and Nintendo.