How and where will revisions and / or modifications to safety data sheets be communicated?

Answer:

If the hazard classification is affected (section 2), a new version is generated with a new date of issue, revision date and supersedes date.

In cases of safety data sheet modifications which do not affect the hazard classification, changes are detailed in section 16. The version number remains the same.

The EDQM also provides its users with a cumulative list containing all classification modifications. This list is available here.