Dollar General investors approved a resolution Wednesday to create an independent audit of the chain's safety policies because of violence at stores and millions of dollars in fines for workplace safety violations.

The third-party audit should evaluate "management and business practices that contribute to an unsafe or violent environment" the resolution said. It said that "understaffing and poor security measures at Dollar General stores may also contribute to increased risk of gun violence to staff and communities."

The vote to audit the company's practices was a rebuke to Dollar General's leadership and a sign of growing pressure on the fast-growing retailer to improve workplace safety. Dollar General has more than 19,000 stores and 160,000 employees.

Since 2014, there have been 49 workers and customers killed and 172 injured at Dollar General stores, according to data from non-profit group Gun Violence Archive. The Labor Department has proposed more than $21 million in fines against Dollar General since 2017 for safety hazards in stores, such as blocked fire exits and electrical outlets and boxes stacked up aisles. The agency deemed Dollar General a "severe violator" of workplace safety laws last year.

Dollar General's board of directors had recommended shareholders vote against the resolution, which was introduced by progressive investment firm Domini Impact Investments and worker advocacy groups.

"A majority vote supporting an independent audit on worker health and safety is a win for Dollar General workers," said Mary Beth Gallagher, director of engagement at Domini, in a statement Wednesday. "We hope the company will act quickly to conduct an independent audit, incorporating worker and customer input."

A Dollar General spokesperson told CNN that the company was awaiting the final results of the proposal and would report it in an SEC filing. The company did not say whether it will conduct the audit.