What must be established if MSDS access is primarily through electronic methods?

The correct answer emphasizes the importance of having a back-up system for accessing Material Safety Data Sheets (MSDS) when the primary mode of access is electronic. This is crucial because electronic systems can experience failures due to power outages, system errors, or network issues. In such cases, workers must still be able to access vital safety information regarding hazardous materials.

Implementing a back-up system ensures that personnel have alternative means to obtain MSDS information in a timely manner, which is essential for maintaining safety standards and compliance with regulations. This could include printed copies of the MSDS, access to another system, or other reliable methods that ensure uninterrupted access to critical safety data.

While other options like additional training, verbal communication systems, and comprehensive manuals are important in the overall safety and information sharing framework, they do not directly address the immediate need for continual access to safety information in case of an electronic system failure.