In the annual report (PDF download), Apple's eighth such publication, the company said it enforced its strict Supplier Code of Conduct through 451 audits, training and education.
Apple suppliers achieved an average 95 percent compliance rate with the maximum 60-hour work week, often a bone of contention for human rights groups that come down hard on Chinese labor practices. That number is up from 92 percent a year ago.
In addition to the usual maintenance and improvements, Apple will also be keeping a closer eye on where suppliers source their minerals. Apple is looking to steer clear of "conflict minerals," or materials sourced from the Democratic Republic of the Congo, the sales of which are used to fund fighting in the region.
This new initiative will be an extension of the report that already covers workers' rights and environmental issues relating to the manufacture of Apple products.
From the report:
The ethical sourcing of minerals is an important part of our mission to ensure safe and fair working conditions. In January 2014 we confirmed that all active, identified tantalum smelters in our supply chain were verified as conflict-free by third party auditors, and we're pushing our suppliers of tin, tungsten, and gold just as hard to use verified sources. To heighten smelter accountability and help stakeholders follow our progress, we are releasing, for the first time, a list of the smelters andrefiners in our supply chain along with their verification status.
In an interview with Financial Times, Apple SVP of Operations Jeff Williams said that January was the first time the company was able to verify that all of the tantalum used in its devices -- for capacitors and resistors -- came from non-conflict zones.
While the electronics industry is responsible for over half of the world's tantalum consumption, it is not a major player in the use of tin, tungsten and gold, meaning actions from companies like Apple will have little impact on smelters of those minerals. Apple will instead use its high-profile brand to spotlight suppliers' smelters in a quarterly report (PDF download), noting which firms do or do not comply with "ethical sourcing guidelines."
So far, 59 smelters were found to be compliant, while another 23 are part of the Conflict-Free Smelter Program. More work can be done, however, as the status of 104 smelters is unknown. The CFSP is an initiative of the Electronic Industry Citizenship Coalition (EICC), which counts Apple, Microsoft, IBM, HP, Sony and Dell among its members.
"We think it has the chance to make a difference," Williams said. "The smelters are a choke point where all this flows through. If we can get as many smelters verified [as possible] through this pressure, then we have a real chance of influencing the various activities on the ground."