OSHA modified the Hazard Communication Standard (HCS) to adopt the GHS to improve safety and health of workers through more effective communications on chemical hazards.

This revised standard improves the quality and consistency of hazard information in the workplace by providing easily understandable information on appropriate handling and safe use of hazardous chemicals.

The first effective date for training on these standards occurred December 1, 2013. The next phase-in dates are June 1, 2015 and December 1, 2015.

What is the phase-in period in the revised Hazard Communication Standard?

The table below summarizes the phase-in dates required under the revised Hazard Communication Standard (HCS):

Effective Dates for HCS

During the phase-in period, employers are required to be in compliance with either the existing HCS or the revised HCS, or both. OSHA recognizes that hazard communication programs will go through a period of time where labels and SDSs under both standards will be present in the workplace. This will be considered acceptable, and employers are not required to maintain two sets of labels and SDSs for compliance purposes.


  • Hazard Communication: The standard that gave workers the right to know, now gives them the right to understand