Labels and MSDS-Environmental Health & Safety - Carnegie Mellon University

Labels and MSDS


Requirements for labeling of chemicals are different for laboratories as compared to the requirements for non-laboratory areas. Check the respective information for your situation from the links on the left side of this page.

One of the requirements manufacturers have when they supply the chemicals you buy is to put a proper and complete label on the container. By law, they must indicate the name of the product and list the hazardous ingredients present. The label must also provide information regarding the hazards associated with using the material. This is often done both with text information as well as with symbols. There are two common symbols used on labels to quickly provide information of the relative hazards of a material. One is called the National Fire Protection Association (NFPA) warning diamond, which appears below as Figure 1. The other is the Hazard Materials Information System (HMIS) system, which appears below as Figure 2. Both systems use a numerical rating of hazards in each of three sections (health hazard, fire/flammability hazard and reactivity hazard). The key to the hazards associated with the numerical ratings is provided below.

Figure 1
Figure 1
Figure 2
Figure 2
Health Hazard Ratings: 0 - Ordinary combustible hazards in a fire
1 - Slightly hazardous
2 - Hazardous
3 - Extreme danger
4 - Deadly
Flammability Hazard Ratings: 0 - Will not burn
1 - Will ignite if preheated
2 - Will ignite if moderately heated
3 - Will ignite at most ambient conditions
4 - Burns readily at ambient conditions
Reactivity Hazard Ratings: 0 - Stable and not reactive with water
1 - Unstable if heated
2 - Violent chemical change
3 - Shock and heat may detonate
4 - May detonate


All persons working with hazardous materials must have easy access to the Material Safety Data Sheets (MSDS) for EACH of those materials. Carnegie Mellon allows those responsible (supervisor, researcher or instructor) for a given work area to meet this requirement in two different fashions.

  1. The MSDS may be present in paper form in the work area, where all applicable persons have access to them.
  2. The MSDS may be accessed through the internet, PROVIDED that it has been confirmed that MSDS for all materials are available in this fashion AND that all applicable employees have access to the internet and are able to obtain MSDS in this way.

***There are new pictograms now in use and additional information on MSDS.  Look for this information in our Fact Sheets section under "Chemical Safety".***