As a business owner, you have a duty to secure the workplace for your employees. And you have rights as a property owner or lessee to control who’s hanging around your business.

But under the new “walkaround” rule from the Occupational Safety and Health Administration (OSHA), third-party representatives of employees would be allowed to accompany OSHA compliance officers during routine workplace inspections.

The U.S. Chamber of Commerce filed a lawsuit Tuesday against OSHA, arguing that the rule gives union organizers, activists, plaintiff’s attorneys and even competitors access to workplaces under the guise of “assisting” inspectors.

As the U.S. Chamber points out, the new rule upends more than 50 years of precedent by expanding the type of third parties allowed to accompany inspectors during walkarounds.

The OSH Act permits employee representatives to accompany the inspectors, which was generally limited to employees themselves, with very limited exceptions.

The presence of these third parties can expose companies to excessive lawsuits and unionization efforts, cause disturbances, reveal confidential business information and raise safety concerns, according to the U.S. Chamber.

“OSHA’s new walkaround rule is the Administration’s latest regulation to take a ‘whole-of-government’ approach to promoting unionization at all costs,” said Marc Freedman, vice president of the U.S. Chamber of Commerce’s Employment Policy Division. “OSHA claims this rule is about workplace safety, but as some union organizers have publicly admitted this rule is about gaining access to nonunionized workplaces to advance their organizing campaigns.”

The Chamber is joined by co-plaintiffs including the Associated Builders and Contractors, Alliance for Chemical Distribution, Associated General Contractors, International Franchise Association, International Warehouse Logistics Association, National Association of Manufacturers, National Federation of Independent Business and National Retail Federation.