What does the class number of lasers indicate?

The class number of lasers is primarily designated to indicate the degree of hazard associated with direct eye exposure. Each class corresponds to specific safety guidelines and risks related to laser usage. For example, Class I lasers are considered safe under all conditions, while higher class numbers indicate increasing risks and require more stringent safety measures to protect against eye injury and skin exposure. This classification system helps users and safety professionals understand how to use lasers safely, taking into account their potential dangers.

The other choices relate to features or characteristics of lasers, such as cutting capabilities, maximum temperatures, or wavelength ranges, but they do not pertain to the classification system and the associated safety hazards concerning eye exposure.