OSHA’s updated Hazard Communication Standard (HCS 2024) has been in effect since 2024, and an important compliance deadline is approaching. 

By November 20, 2026, employers must complete required HCS 2024 updates for substances. This includes updating workplace labels, revising written hazard communication programs and providing additional employee training when new hazards are identified. 

For companies managing hazardous chemicals, now is the time to make sure updated Safety Data Sheets (SDSs) and hazard information are reflected in workplace practices.

Understanding the HCS 2024 Timeline 

OSHA updated the Hazard Communication Standard to better align with Rev. 7 of the Globally Harmonized System (GHS). The changes affect chemical classification, labeling and SDS requirements. 

In January 2026, OSHA extended its compliance deadlines by four months, giving organizations additional time to prepare. 

Here are the key dates: 

• May 19, 2026: Manufacturers, importers and distributors must comply with updated requirements for substances. 

• November 20, 2026: Employers must complete necessary workplace updates for substances. 

• November 19, 2027: Manufacturers, importers and distributors must comply with updated requirements for mixtures. 

• May 19, 2028: Employers must complete necessary workplace updates for mixtures. 

The phased approach gives employers additional time to address mixtures, but the November 2026 deadline for substances is quickly approaching. 

What Should Employers Be Doing Now? 

Meeting the November deadline starts with understanding what has changed in your chemical inventory. 

Employers should review their SDS libraries, confirm that updated documents have been received from suppliers and determine whether revised hazard classifications require changes to workplace labels, written programs or employee training. This can be challenging for organizations managing hundreds or thousands of chemicals across multiple facilities. 

This is where having a centralized system for SDS and chemical data management makes a difference. Lisam helps organizations organize chemical information, manage SDS updates and improve visibility into chemical inventories across facilities, reducing the manual effort required to maintain accurate hazard information.

Preparing for November and Beyond 

November 20 is the compliance deadline, not the starting point. Organizations should use the remaining time to review their substance inventories, identify gaps and complete any necessary updates. 

For organizations managing thousands of chemicals across multiple facilities, receiving an updated SDS is only part of the challenge. Compliance teams also need to determine what changed, identify which facilities use the chemical, and ensure affected employees can access the correct hazard information.

Lisam’s chemical management solutions help connect these activities by bringing SDS information and chemical inventory data together, making it easier to manage changes and maintain consistent information across locations.

With additional HCS 2024 requirements for mixtures approaching in 2027 and 2028, establishing a reliable chemical data management process now can also simplify future compliance efforts. 

HCS 2024 is ultimately about ensuring employees have accurate, up-to-date information about the chemicals they work with. Taking action now can help employers meet the November deadline while strengthening chemical safety management for the long term.

HCS 2024 Resources

Final rule: https://www.federalregister.gov/documents/2024/05/20/2024-08568/hazard-communication-standard
Correction (10/09/2024): https://www.federalregister.gov/documents/2024/10/09/2024-23144/hazard-communication-standard
Correction (01/08/2026): https://www.federalregister.gov/documents/2026/01/08/2026-00147/hazard-communication-standard-corrections
GHS(Rev.7) (2017) | UNECE
GHS(Rev.8) (2019) | UNECE
GHS(Rev.9) (2021) | UNECE