Human hazards are those hazards caused directly or indirectly by human action or inaction. They can be contrasted with natural hazards. Anthropogenic hazards may adversely affect humans, other organisms and biomes and eco-systems. The frequency and severity of hazards are key elements in some risk analysis methodologies. Hazards may also be described in relation to the impact that they have. Environmental hazards may be very different from human hazards. A hazard only exists if there is a pathway to exposure. As an example the center of the earth consists of molten material at very high temperatures which would be a severe hazard if contact was made with the core. However, there is no feasible way of making contact with the core, therefore the center of the earth currently poses no hazard.
Societal hazards occur when the behavior of individuals or groups of individuals give rise to a reasonable apprehension of injury or death.
Behavior which puts others at risk of injury or death is universally regarded as criminal and is a breach of the law for which the appropriate legal authority may impose some form of penalty, such as imprisonment, a fine, or even execution. Understanding what makes individuals act in a way that puts others at risk has been the subject of much research in many developed countries. Mitigating the hazard of criminality is very dependent on time and place with some areas and times of day posing a greater risk than others.
Civil disorder is a broad term that is typically used by law enforcement to describe forms of disturbance when many people are involved and are set upon a common aim. Civil disorder has many causes, including large-scale criminal conspiracy, socio-economic factors (unemployment, poverty), hostility between racial and ethnic groups and outrage over perceived moral and legal transgressions. Examples of well-known civil disorders and riots are the Poll Tax Riots in the United Kingdom in 1990; the 1992 Los Angeles riots in which 53 people died; the 2008 Greek riots after a 15-year-old boy was fatally shot by police; and the 2010 Thai political protests in Bangkok during which 91 people died. Such behavior is only hazardous for those directly involved as participants or those controlling the disturbance or those indirectly involved as passers-by or shopkeepers for example. For the great majority, staying out of the way of the disturbance eliminates the hazard.