4. Classification based on their origin

Hazards can be grouped into eight categories

 Hazards that are created in the atmosphere pose a danger to human health and wealth.

A geologic hazard is extreme natural events in the earth's crust that pose a threat to life and property.

Hydrological hazards are hazards involving water processes.

A volcanic hazard is defined as any potentially dangerous volcanic process that puts human lives, livelihoods or properties at risk of harm.

'Environmental hazards' are events that have the potential to threaten the surrounding natural environment and adversely affect people's health.

Biological organisms like pathogenic micro-organisms, toxins and bioactive substances that pose a threat to human life, property, socio-economic disruption are called biological hazards.

The UNISDR definition of technological hazards refers to hazards that stem from technological or industrial conditions like accidents, infrastructure deficiencies, and specific human activities that can cause loss of life, injury, disease, or other health impacts.

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