Globally Harmonized System (GHS)

What is it? 

A Globally Harmonized System (GHS) for Hazard Classification and Labelling. It is an international, standardized approach to hazard communication. The introduction of this system ensures that chemical users worldwide will understand the labeling and hazard identification associated with chemicals. The criteria for classification of chemical hazards, chemical labels and Safety Data Sheets (SDS, formerly Material Safety Data Sheets (MSDS)) are all going to follow a standard set of rules. This change has been described as moving from 'the right to know' to 'the right to understand'.

What does it mean for me?

GHS provides a common, coherent approach to defining and classifying chemical hazards and the protective measures necessary to prevent exposure. It requires standard labels for all chemicals regardless of manufacturer. This is the first and most obvious change you will see. Each label has; the chemical name, a signal word, a hazard statement, pictograms representing the hazards associated with the chemical, precautionary statements and the name and address of the manufacturer.

Click here for an example label.

Signal Words: Danger and Warning
The two signal words that are on every label are 'Danger' and 'Warning'. What you need to know is that chemicals with the signal word 'Danger' pose the greater hazard.

Hazard Statements: Key Words
Hazard statements on chemical labels describe the nature of the hazard with key words indicating the severity of the hazard.
Click here to see example hazard statements.

Standard pictograms are used to represent the physical and health hazards related to each chemical.
Click here to see the GHS pictograms.

Safety Data Sheets

The next significant change was Safety Data Sheets replaced Material Safety Data Sheets. Unlike the former MSDS, the SDS format has been standardized. All manufacturers were required to provide safety information in the same format. This makes it easier to find the pertinent information needed to handle a chemical safely. Click here for a list of the SDS sections.

Hazard Ratings - Significant Change!!!

Be aware of the fact that a significant change has occurred with respect to hazard ratings under GHS. Numeric hazard ratings in GHS are the OPPOSITE of what they were with the Hazardous Materials Identification System (HMIS) and the National Fire Protection Agency (NFPA). Now, the lower the rating, the higher the hazard! The numeric hazard ratings for a chemical is included on the SDS. In most cases, this should be found in the Hazards Identification section (section 2). Recent experience however has shown that this may not be the case for every SDS. Hazard ratings have also been found in section 15 (Regulatory information) and section 16 (Other information).

Click here for a visual reference regarding this change. It will be very important to pay attention to which numeric system is being used!

What about other agencies?

The Department of Transportation (DOT), Environmental Protection Agency (EPA) and the Consumer Product Safety Commission all took part in developing the GHS. The DOT has modified its classification and labelling requirements to be in line with the new system.

The National Fire Protection Agency (NFPA) has a separate system for classifying chemical hazards. This system will NOT be changing. As GHS reaches full implementation there may come a need to slightly modify the NFPA system but it will not go away. The agencies are depending on individuals being trained and made aware of the differences in order to prevent confusion. As an individual working with chemicals, the most important thing to remember is that the numeric hazard classifications used in the two systems are opposite one another.


It is especially important to know if you are looking at hazard information from GHS, NFPA or HMIS. If you have questions - ASK!

The intent of GHS is to ensure hazard classifications are consistent and standardized on an international level. This will help prevent workplace injuries, illnesses and fatalities while ensuring the safe use of chemicals from cradle to grave.