Probing crowd density through smartphones in city-scale mass gatherings

EPJ Data Science

Table 1 Chart of crowd density

Dynamics	Density [ $m^{- 2}$ ]	Behavior and risk
Standing	7.1	Critical crowd density for static crowds
Walking	0.43	Stream of pedestrians can maintain normal walking speed and avoid one another
	2	Walking speed is reduced
	3.57	Involuntary contact is experienced between people
	5.55	Potentially dangerous crowd forces begin to develop

Chart derived from the findings of Fruin [23] to assess the criticality of a crowd density. The density of a static crowd can exceed the density of a moving crowd before a critical values is reached.