OSHA General Duty Clause.
You are likely familiar with OSHA and the safety rules it sets forth. And you also likely know that OSHA can enforce those express safety rules in non-complying conditions. But did you know that OSHA can issue citations for unsafe conditions not specifically listed in its safety rules?
The OSHA General Duty Clause, Section 5 (29 USC 654) requires an employer to provide a workplace free of recognized hazards that are causing or likely to cause death or serious harm to employees.
So if you think a condition or behavior may result in injury, regardless of whether or not OSHA rules specifically address the condition or behavior, OSHA can enforce via citation.