GHS Hazard Classifications & Categories

ghs classification for isopropyl alcoholA main purpose of the new GHS is to standardize the types of chemical hazards that exist and the way entities in the chemical industry classify chemicals that have those hazards. Prior to GHS, the same chemical could be classified differently in different countries and industries, resulting in confusing standards. To that end, the GHS names three main hazard groups: physical, health, and environmental.

Physical hazards: The chemicals and substances in this class pose a threat that could injure people or damage property. For example, a gas might explode, causing physical damage. This classification is predominately based on the United Nations Dangerous Goods System. The physical hazards as defined by GHS include:

  • Explosives
  • Flammable Gases
  • Flammable Aerosols
  • Oxidizing Gases
  • Gases Under Pressure
  • Flammable Liquids
  • Flammable Solids
  • Self-Reactive Substances
  • Pyrophoric Liquids
  • Pyrophoric Solids
  • Self-Heating Substances
  • Substances which, in contact with water emit flammable gases
  • Oxidizing Liquids
  • Oxidizing Solids
  • Organic Peroxides
  • Corrosive to Metals

Health hazards: Materials that impact human health by causing irritating symptoms or even deadly diseases are classified as a health hazard. If a chemical poses a serious risk due to exposure, it will need to be labeled accordingly. The following are characteristics of a health hazard:

  • Acute Toxicity
  • Carcinogenicity
  • Skin Corrosion/Irritation
  • Reproductive Toxicity
  • Serious Eye Damage/Eye Irritation
  • Target Organ Systemic Toxicity- Single Exposure
  • Respiratory or Skin Sensitization
  • Target Organ Systemic Toxicity- Repeat Exposure
  • Germ Cell Mutagenicity
  • Aspiration Toxicity

Environmental hazards: A chemical or substance that poses the risk to negatively impact aquatic environments are classified as an environmental hazard. This includes:

  • Acute Aquatic Toxicity
  • Chronic Aquatic Toxicity

Each general group is divided up into more specific classes, and each class into even more specific categories. (Details about the classes and categories can be found in the GHS Purple Book.)

Why is classification important?

Properly classifying the chemicals, you are working with help you in creating a compliant label and an appropriate safety data sheet (SDS). Without accurate classification, your facility can face fines or other penalties determined by OSHA.

Usually the first component of a chemical label that is seen and understood is the use of hazard pictograms. Chemical labels also include a hazard statement, typically a designated code for the hazard class that corresponds with the classification. Having the right classification will also ensure you include the correct corresponding symbol. There are specific pictograms for health hazard and environmental hazard, but other OSHA-acceptable symbols include:

  • Flame: Used for flammable solids, liquids, and gases.
  • Exclamation mark: Used for substances that can cause any type of damage to skin or eyes.
  • Gas cylinder: Used to mark any gases that are contained under pressure.
  • Corrosion: A specific symbol meaning the chemical can corrode metal or flesh.
  • Exploding bomb: Denotes the explosive materials or self-reactive substances.
  • Flame over circle: Represents gases or liquids that will oxidize.
  • Skull & crossbones: Indicates toxic chemicals and substances that can cause significant danger with limited exposure.

Additionally, the hazard classification will provide the information you will need to fill out an SDS. It includes first-aid information, storage information, chemical properties, toxicological information, ecological information, etc. By properly classifying the chemical you can keep you workers safe by providing the important information about the substance.

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