According to regulations, when is entry into a confined space considered to have occurred?

Entry into a confined space is considered to have occurred when any part of the entrant's body breaks the plane of an opening. This definition emphasizes that the act of entry is not merely about preparing or equipping oneself but specifically about physically crossing the threshold into the confined space. Once an individual’s body enters the space, they are in a different environment with its own risks and hazards, which necessitates the application of confined space protocols and safety procedures.

This understanding is important because it sets the stage for when the requirements for safety measures, monitoring, and other protective actions must be initiated. It underscores that being in a confined space carries different regulatory obligations compared to just preparing to enter or being near the entrance, making it crucial for safety compliance.