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. The standard deviation measures the spread of the data around the mean. See: Measures of Spread. Standard error (SE). The standard error (SE) is a measure of the variation between any estimated population value that is based on a sample rather than true value for the population.