# Water and Wastewater Terms Beginning L

A B C D E F G H I J K L M N O P Q R S T U V W Y Z

# logarithmic scale (LOG-uh-RITH-mick)

A scale on which each equal increment increases by a factor of 10 (e.g., 100, 101, 102) instead of by 1 (e.g., 1, 2, 3, 4), and the corresponding numbers are 100 = 1, 101 = 10, 102 = 100, etc. For numbers less than 1, the corresponding numbers are 10-1 = 0.1, 10-2 = 0.01, 10-3 = 0.001, etc. On a logarithmic scale, there are no zero or negative values. Instead, the scale starts with the smallest positive factor of 10 desired to display the data. This type of scale is typically used to display skewed data and show relative differences.