With solid materials, when are labels not required to be included with subsequent shipments?

Labels for solid materials are not required to be included with subsequent shipments unless the information on the label changes. This requirement is rooted in the goal of maintaining consistent communication regarding hazards and safety information. If the information—such as the chemical composition, hazard classification, or safety instructions—remains the same, there is no need to provide a new label with each shipment, as the original label already contains the necessary information to ensure safety during handling and use.

In the context of Hazard Communication, consistent labeling helps in ensuring that workers and emergency responders have access to the same hazard information for the materials they may encounter across different shipments. If the information changes, however, updated labels would be necessary to reflect those changes and provide accurate safety information. This helps in preventing accidents and ensuring that everyone handling the materials is aware of any new risks or handling requirements.

The other options suggest scenarios where labels might not be necessary, but they do not align with the fundamental principle of maintaining accurate hazard communication through labeling. For instance, delays in shipments or customer requests do not exempt the requirement for labeling; the consistent communication of hazard information is paramount regardless of logistical factors.