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.
The standard deviation describes the spread of the data, and is the basis for how we compute things like the degree of certainty, the margin of error, etc. Suppose we have a population of data points, P={p1,â¦,pn}. We know that the mean is. the sum of the points (pis) divided by the number of.