A preliminary audit commissioned by Apple found Chinese factories that make components for Apple products have improved working conditions for their employees.

The Fair Labor Association (FLA) has started inspecting the working conditions of Apple's suppliers in China and is going to report the results in early March.

The investigation comes on the heels of the supplier responsibility report Apple released in January. The reputation of Foxconn, Apple's largest supplier, has been tarnished by an explosion at its Chengdu plant as well as by frequent media reports about worker suicides, dangerous conditions and overworked employees.

FLA president Auret van Heerden did not draw a full picture of working conditions at Foxconn, but he described facilities at those plants as "very modern and very high tech" after visiting two factories in Shenzhen and another in the southwestern city of Chengdu.

"There was definitely a problem with aluminum dust (that led to an explosion at the Chengdu plant in May last year). After that, they developed a new technology to extract and recycle the dust," Heerden said.

After reports came out that a hazardous chemical used to polish iPad parts can cause neural diseases, Foxconn began using robots instead of workers for this job, he said.

The audit used an iPad to collect responses to questions from 3,500 workers at Foxconn plants during interviews. Questions covered matters such as hiring and firing policies, dorm conditions and mental health.

The FLA mobilized 30 Chinese labor experts to perform the audit.

"Foxconn welcomes a third-party organization to evaluate our employment, production and workers' living standards," said Liu Kun on behalf of Foxconn Technology Group.

Liu said his company would help FLA carry out the investigation and would not intervene in the questionnaire and interview process.

The company did not inform workers of the audit in advance but "just asked them to pay attention to their personal hygiene", Liu said.

"We never ignore different voices from workers. Voices, be they positive or negative, can reveal workers' real feelings and thoughts," he said. "We expect a fair and objective evaluation."

In response to questions over the FLA's objectivity, Heerden said: "We have independent access that allows us to go to any facilities we want to visit, and we own the intellectual property of what we collect, and we can publish it.

"The data would not go through anybody else's hands - neither Foxconn nor Apple. Transparency is the best protection of our independence."

FLA has more than 200 members, including 34 companies. The organization charges membership fees each year from its corporate members. Apple recently became a member of FLA. Among FLA's board of directors are six entrepreneurs, according to China Business News.

"I can see that there's been so much bad news about Foxconn in the media, but I do believe we have reached a turning point with Foxconn. I think they are determined to get this right," Heerden said.

Huang Leping, head of the non-governmental organization Beijing Yilian Legal Aid and Study Center of Labor, said Apple's involvement in the investigation shows that the company has acknowledged that it has encountered problems in labor protection at the supplier level.

Huang suggested that more NGOs, especially Chinese ones, should be introduced to jointly carry out the audit to make results fairer and reflect the real working conditions at Apple's Chinese suppliers, because standards may vary in different agencies.

Content, procedure and names of the experts that carry out the audit should also be open to the public to make the investigation more transparent and reliable, he added.