Every country has their own regulations on MSDS sheets and possible expiration dates.
Canadian WHMIS MSDS sheets expire every 3 years. The MSDS sheet must be updated to provide any new information that has become available since the date it was first prepared. This may include a change in the formulation or information that has demonstrated a hazard that was not previously stated.
United States OSHA MSDS sheets have no specific requirements concerning expiration dates. However, as required by OSHA, a new MSDS sheet must be issued if any of these conditions are met:
There has been a significant change to the chemical makeup
A health or physical hazard that is different from previously stated is discovered
If the product has been listed as carcinogenic
If any of these changes occur, a new MSDS must be released with the new date that it was prepared on.
In the European Union, under the old CLP regulations SDS sheets also do not have a specific expiration dates. However, if any information has been added, deleted or revised, this must clearly be shown on the revised sheet.
Each of these three countries does require the date of preparation or date of revision to be listed on the current MSDS sheet in place. Even if your country does not have an expiration date in place, it is best to review your MSDS sheets regularly to ensure proper compliance.