âº EVC System. A disabled refuge is a relatively safe area within a building or exit staircase for mobility impaired occupants, allowing building management and emergency services to safely assist these people from the building.
Standard deviation is a number used to tell how measurements for a group are spread out from the average (mean), or expected value. A low standard deviation means that most of the numbers are very close to the average. A high standard deviation means that the numbers are spread out.
Standard deviation is a measure of how spread out numbers are from the average of a data set. It is not the same as average or mean deviation or absolute deviation, where the absolute value of each distance from the mean is used, so be careful to apply the correct steps when calculating deviation.