Introduction The temporary workforce in the United States, which experienced a 161% increase from 2009 to 2016, now numbers nearly three million. Metropolitan Chicago is a hub in the increasingly industrial temporary services industry (TSI), with a plethora of temporary staffing agencies providing domestic and multinational corporations with a pool of immigrant and African American employees who work in low paying, hazardous factory and warehouse jobs.

The goals of this project were to enhance the capacity of grassroots non-profit worker advocacy organisations known as workers centres to identify workplace hazards encountered by such temporary workers, raise workers’ awareness of their rights to a healthy and safe workplace, and take action to achieve safer working conditions.

Methods In 2015 two Chicago area worker centres, collaborating with university partners, trained fourteen temporary worker-member activists on workplace safety rights and how to conduct surveys of worksite hazards with other temporary workers.

Results Ninety eight workers were surveyed over six weeks. Respondents reported serious hazards, including repeated and heavy lifting, inadequate machine guarding and unsafe forklifts, as well as issues with discrimination and unfair wages. 20% had been injured and 40% had not received any job-task or general health and safety training.

Discussion Through this project, the worker centres expanded their database of working conditions and employment abuses in the local TSI, began building a corps of worker leaders to educate peers about safety issues, supported workers in taking legal action to address these conditions, and planned future safety organising campaigns.