According to OSHA, which safety measure must be followed in a laser treatment room?

Warning signs must be prominently displayed on treatment doors in a laser treatment room as a critical safety measure mandated by OSHA. This requirement serves to alert individuals who enter the area about the potential hazards associated with laser equipment. The presence of warning signs plays a vital role in ensuring that untrained or unauthorized personnel are warned of the risks, particularly since laser treatments can pose serious health hazards such as skin and eye injuries. By informing everyone that lasers are in use, these signs help prevent accidental exposure and enhance the overall safety of the environment.

In the context of the other options, while it’s important that only trained personnel enter the treatment room and that no food or drinks are allowed to maintain hygiene, these measures do not encompass the broader necessity of providing a clear warning about the dangers present. Leaving lasers on during breaks is fundamentally unsafe and not compliant with protective practices aimed at preventing accidents. The requirement for warning signs is foundational to creating a safe space where risk is minimized.