What are the hazard classes under the GHS rules?

The hazard classes under the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) are categorized into physical hazards, health hazards, and environmental hazards. This classification is designed to ensure that the hazards of chemical products are communicated consistently and effectively across different countries and regions.

Physical hazards include aspects such as flammability, explosivity, and reactivity, which indicate how the substance behaves under specific conditions. Health hazards represent the potential effects chemicals may have on human health, including toxicity, irritation, and sensitization. Environmental hazards refer to the potential impacts chemicals may have on aquatic and terrestrial ecosystems. This classification system is vital for improving safety standards and protecting human health and the environment.

The other choices do not accurately reflect the established classes under the GHS. For instance, the combination of electrical, structural, and toxicological hazards does not fit the GHS framework, and continuous, intermittent, and negligible are not recognized categories in the context of chemical hazard classification.