What Does 95th Percentile Mean?
The term 95th percentile refers to the point at which 5% of a population set will exceed the referenced value. To determine the percentile value, a set of variables is divided into 100 equal groups. In ergonomics, the 95th percentile is a statistical value often used to determine the upper anthropometric dimension, or body size, boundary value for ergonomic designs.
WorkplaceTesting Explains 95th Percentile
To determine the 95th percentile of a set or population, the variables of that set are translated into 100 percentage categories from lowest to highest. The 95th percentile then represents the point at which 5% of the study set exceeds that value assigned to the 95th percentage category.
For the purpose of ergonomics, the 95th percentile represents the upper boundary for design and effectiveness considerations. When determining the range of usability for ergonomic designs, the anthropometric dimensions, or physical measurements, of a population are divided into 100 groups. Each of these 100 groups represents a percentile.
It is important to note that in ergonomics design, this 95th percentile value is based on the measurements of male members of the population. Because women tend to be smaller than men, the physical dimensions of a person who is in the 95th percentile will be greater than 95% of all males in the target population and is assumed to statistically encompass 100% of all females.
Commonly, ergonomic designs are created to suit a range of sizes from the 5th percentile female dimension value to the 95th percentile male dimension value. Those individuals who fall outside this range may need special accommodations to achieve optimal ergonomic benefits.