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.
By Courtney Taylor. Definition: The standard deviation measures how spread out a data set is from its mean. The standard deviation is the square root of the variance of a data set, and is calculated by this formula.Examples: 1  The data set 2,2,2,2,2 is not spread out at all, and has standard deviation of zero.2  The data set 2,3,4,4,5,6 has standard deviation of approximately 1.4.he standard deviation is the square root of the variance of a data set, and is calculated by this formula. Examples: 1  The data set 2,2,2,2,2 is not spread out at all, and has standard deviation of zero. 2  The data set 2,3,4,4,5,6 has standard deviation of approximately 1.4.